Alcohol 20 (2000) 61–68
Haloperidol administered subchronically reduces the alcohol-deprivation effect in mice R.M. Salimov*, N.B. Salimova, L.N. Shvets, A.I. Maisky Institute of Pharmacology, Russian Academy of Medical Sciences, Moscow, 125315, Russia Received 15 October, 1998; received in revised form 7 April, 1999; accepted 6 July, 1999
Abstract During the pre-experimental phase, hybrid (CBA 3 C57BL) male mice having had 16 weeks free access to food, water and flavored 30% alcohol were deprived of alcohol for 3 days. The next day they were given free choice between similarly flavored water and 30% alcohol. The mice were divided into two subgroups having (HD) or lacking (LD) the deprivation-induced elevation in alcohol intake during the first 1.5 h of renewed access compared with their intake during the last 22.5 h of first postdeprivation day. In Experiment 1, alcohol naive, LD, and HD mice received daily injections of haloperidol (Haldol; 1 mg/kg) or vehicle during 14 days of abstinence. The behavior of the mice was evaluated in an exploratory cross-maze and inescapable slip funnel test a day after the 13th injection (before the 14th injection). On the first postinjection day, the mice were again given a free choice between flavored water and alcohol. In Experiment 2, all the mice were administered with vehicle during the first 13 days of abstinence. On 14th day, they received an injection of haloperidol (1 mg/ kg) or vehicle and a day later were given choice between flavored water and alcohol. Unlike a single injection, the subchronic administration of haloperidol lowered the alcohol intake by HD mice with a more prominent decrease seen during the first 1.5 h than during the last 22.5 h of first postdeprivation day. The alcohol-deprivation effect in HD mice decreased by 79% after subchronic haloperidol. No significant change in alcohol intake was found in alcohol-naive and LD mice. Water intake did not vary systematically. Among the groups, the effect of subchronic haloperidol on the alcohol-deprivation effect did not parallel changes in most of the measures of exploratory or avoidance behavior. It is proposed that haloperidol administered subchronically may attenuate motivation for alcohol. © 2000 Elsevier Science Inc. All rights reserved. Keywords: Mouse; Alcohol drinking; Exploratory behavior; Avoidance; haloperidol; Motivation
1. Introduction Dopamine has been thought to be one of the neurotransmitters playing an important role in reinforcement, craving and incentive motivation with various drugs of abuse, including ethanol (McBride et al., 1990; Wise & Bozarth, 1987), although some authors believe that dopamine is not critical for ethanol reinforcement (Amit & Brown, 1982; Rassnick et al., 1993b). A linkage between a relatively low level of dopamine neurotransmission and the alcohol drinking has been suggested for several rodent lines that are genetically predisposed to drink alcohol (McBride et al., 1993; Ng et al., 1994; Stefanini et al., 1992). Some pharmacological manipulations affecting dopamine neurons, however, have had discrepant outcomes. Several studies have reported an increase in the consumption of alcohol after microinjection of a neurotoxic drug 6-OHDA into the brain (Myers, 1990; Quarfordt et al., 1991) or decrease in the alcohol intake dur* Corresponding author. Tel.: 17-095-400-7612; Fax: 17-095-400-7612. E-mail address: [email protected]
ing administration of monoamine oxidase inhibitors (Daoust et al., 1986; George et al., 1995; Sanders et al., 1977), whereas others have revealed no effect of the treatments on the alcohol drinking (Daoust et al., 1984; Kiianmaa et al., 1979; Richardson & Novakovski, 1978). Selective activation of dopamine neurotransmission has been found to lower volitional consumption of alcohol. In a continuous access paradigm, administration of dopamine receptor agonists of the D1 (SKF-38393) and the D2 (bromocriptine) type diminished drinking of alcohol in rats and mice (Ng & George, 1994; Silvestre et al., 1996; Stanishevskaia et al., 1985). In a limited access paradigm, administration of D1 (SKF-38393), and D2 (quinpirole, apomorphine, SDZ205,152) agonists reduced alcohol intake by rats with the most prominent decline seen during the first postdeprivation hour (Dyr et al., 1993; Rassnick et al., 1993a; Russell et al., 1996). Inconsistent results were seen during administration of D2 antagonists. Intraperitoneal injections of haloperidol (Haldol) shortly before drinking test reduced the alcohol intake, whereas the treatment with raclopride or spiperone did not change drinking of alcohol (Silvestre et al., 1996). Both increase (Levy et al., 1991) or decrease (Rassnick et al.,
0741-8329/00/$ – see front matter © 2000 Elsevier Science Inc. All rights reserved. PII: S0741-8329(99)00 0 5 7 - 9
R.M. Salimov et al. / Alcohol 20 (2000) 61–68
1992) in alcohol consumption was reported as a result of microinjection of sulpiride or fluphenazine into the nucleus accumbens. Another method for enhancing dopaminergic neurotransmission is the subchronic application of potent dopamine receptor antagonist, which results in long lasting up-regulation of dopamine receptors. Thus, a neuroleptic drug, haloperidol, known as preferential dopamine D2 antagonist, administered at a dose about 1 mg/kg for at least a week elevates the density of D2 binding sites and induces “functional supersensitivity” to dopamine receptor agonists seen during the first 1–3 days after cancellation of the treatment (Goss et al., 1991; MacLennan et al., 1988; Wolffgramm et al., 1990). During that period, the treated animals demonstrate a decrease in motor activity in the exploratory test (Thornburg & Moore, 1975) and increase in avoidance (Rosic & Overstreet, 1982) and climbing behavior (Kuruvilla et al., 1982). Simultaneous treatment with both haloperidol and alcohol prevents both the rise in number of D2 binding sites and the development of the behavioral signs of supersensitivity to dopamine agonists (Fuchs et al., 1987; Wolffgramm et al., 1990). Very little, however, is known with regard to the aftereffect of subchronic dopamine D2 antagonists on alcohol motivation. One rat study employing a continuous access paradigm reported that haloperidol added to the drinking solution (7 mkg/l) reduces preference for alcohol versus water (Fuchs et al., 1987). Another neuroleptic drug, pimozide, administered subchronically, reduced drinking of alcohol by rats in a limited access paradigm (29) but did not change intake of alcohol available continuously (Brown et al., 1982; Goodwin et al., 1996; Pfeffer & Samson, 1986). As a follow-up to these studies, it was the aim of the present investigation to evaluate the effects of haloperidol, administered in accord to a scheme reportedly capable of enhancing dopamine D2 neurotransmission, on what has been called the alcohol-deprivation effect (ADE) in mice. The ADE has been observed in rats (LeMagnen, 1960; Sinclair & Li, 1989; Sinclair & Senter, 1967; Sinclair & Senter, 1968), mice (Salimov et al., 1995a; Salimov & Salimova, 1993a; Salimov & Salimova, 1993b), monkeys (Kornet et al., 1990; Sinclair, 1971), and humans (Banish et al., 1981; Rankin et al., 1979); and it considered as a measure of motivation for alcohol (Eravci et al., 1997; Rankin et al., 1979; Sinclair & Senter, 1967), loss of control (Wolffgramm & Heyne, 1995), or relapse (Kornet et al., 1991; McKinzie et al., 1996) in alcohol-dependent individuals. Not all animals show a positive ADE; golden hamsters, for example, do not increase their alcohol drinking immediately after deprivation, although they are characterized by high drinking of continuously available alcohol (DiBattista, 1991; Sinclair & Bender, 1978). In ethanol-experienced rodents, the ADE may be produced by at least several days of abstinence; it consists of a temporary increase in alcohol intake especially during the first 1–2 h of renewed access to alcohol. In mice (Salimov et al., 1995a; Salimov & Salimova, 1993b) and
monkeys (Kornet et al., 1990; Kornet et al., 1991), the ADE is represented by its initial phase: the rate of alcohol intake elevates during initial 1–2 h of renewed access to alcohol and returns to its pre-deprivation level during subsequent 12–24 h. The ADE is not taste-dependent and can be observed when flavored and strong (up to 32%) alcohol solutions are offered to animals (Kornet et al., 1990; Salimov & Salimova, 1993a; Salimov & Salimova, 1993b). Experiment 1 was aimed to investigate if haloperidol, applied at a dose (1 mg/kg) and for a period (2 weeks) known to enhance dopamine D2 neurotransmission, affects the ADE in mice having had a prolonged access to alcohol previously. To evaluate some of the behavioral signs of dopamine receptor “functional supersensitivity,” an exploratory cross-maze and inescapable slip funnel test have been used. The tests can provide with several independent measures of exploratory, climbing and avoidance behavior (Salimov, 1999; Salimov et al., 1996b; Salimov et al., 1995c) and those of major motor skills. Experiment 2 served as a control for Experiment 1 and was aimed at determining whether the alcohol drinking by mice is altered a day after a single injection of the same dose of haloperidol.
2. Methods 2.1. Animals and general procedure Three hundred hybrid (C57BL/6 3 CBA, F1) naive 2 month-old male mice weighing 20–24 g were purchased from the Laboratory of Experimental Biological Models (Moscow region). The mice were individually marked and housed in group cages (36 3 24 3 10 cm), 5–7 animals per cage, located in a room at 20–248C, and approximately 60% humidity. The light was on from 06:00 till 18:00. The mice were allowed free access to Standard Dry Protein mouse diet and tap water. During the 16-week pre-experimental phase, the mice in the alcohol group had free access to an additional bottle containing 30% (v/v) ethanol (prepared from 96%, Alexin alcohol plant, Russia) flavored with 0.1% saccharin and 0.02% menthol (99% pure, Aldrich, Germany) in their cages. A special stainless steel drinking tip with a 1.5 mm terminal hole was used to prevent alcohol evaporation. Mice of naive group had additional access to similarly flavored water instead of alcohol. Starting on week 13, the position of the bottles was alternated every other day to prevent development of a place preference. All liquids were replaced twice a week. On week 17, mice in the alcohol group were deprived of alcohol for 3 days. During this period, the alcohol solution was replaced by similarly flavored water. At about 9:00 on the first postdeprivation day, the mice were placed for 24 h in individual cages (15 3 4 3 5 cm) containing food and two 10 ml pipettes. One pipette contained 30% alcohol flavored with 0.1% saccharine and 0.02% menthol, and the other pipette contained similarly flavored water. The pi-
R.M. Salimov et al. / Alcohol 20 (2000) 61–68
pettes had a 1.5 3 3 mm terminal hole that opened upward to prevent spillage. The fluid intake was measured 1.5 h and 24 h after the beginning of renewed access to alcohol. Pure alcohol and water intake was calculated as g/kg per hour. Because in mice the ADE is seen during initial 1.5 h of postdeprivation period and during subsequent hours drinking of alcohol returns to its predeprivation level (Salimov et al., 1995a; Salimov & Salimova, 1993a; Salimov & Salimova, 1993b), the difference between amount of alcohol consumed during first 1.5 and last 22.5 h of the first postdeprivation day served as the measure of the ADE. On the basis of this first ADE test, the mice were divided into two subgroups: having (HD) or lacking (LD) the positive ADE. All animals were returned to their home cages with liquids available as before deprivation for the subsequent 10 days. In Experiment 1, three groups of mice were used: the alcohol-naive, LD, and HD mice (n 5 60 for each of the group). From day 1 of week 19 to day 7 of week 20, the LD and HD mice were deprived of alcohol (the alcohol solution was replaced by similarly flavored water). During this 14day period, all the mice received i.p. injections of haloperidol (n 5 30) or vehicle (n 5 30). The injections were made once a day at about 14:00 for 14 days. To evaluate effects of subchronic haloperidol on exploratory and avoidance behavior, all the mice were tested in an exploratory crossmaze and slip funnel test. The behavioral tests were performed on day 7 of week 20 (before the last injection). On the first day of week 21, all the animals were placed in individual cages, where consumption of flavored water and alcohol was again evaluated for 24 h. In Experiment 2, three groups of mice were used: the alcohol-naive, LD, and HD mice (n 5 40 for each of the group). The LD and HD mice were deprived of alcohol for 14 days as in Experiment 1. During this period, all the mice were administered with vehicle during the first 13 days of abstinence (once a day). On 14th day, they received an injection of haloperidol (1 mg/kg) (n 5 20) or vehicle (n 5 20) and a day later were given a choice between flavored water and alcohol. 2.2. Cross-maze test The cross-maze apparatus was made of Plexiglas and consisted of four closed empty arms (numbered 1, 2, 3, 4) connected to a similar central compartment via 7 3 7-cm doorways. The arms and the central box dimensions were 15 3 15 3 15 cm. The floor was cleaned after each animal. The animal was placed into the central compartment and allowed to explore the maze. The sequence and timing of arms visited were recorded directly into a personal computer by an observer until 13 visits had been made (without time limit). The criterion for a visit was entry into a compartment with all four paws inside. Subsequent computer analysis was made to reveal several independent behavioral measures (Salimov, 1988; Salimova et al., 1995b; Salimov & Salimova, 1993b):
1. Total time in arms and central compartment, serving as measures of motor activity. 2. Latency to start exploration (i.e., the time before the first arm entry). This variable negatively correlates with the total time in the open arms in the elevated plus-maze test (Salimov, 1999). 3. Length of first episode of maze patrolling (i.e., number of entries before every arm has been first visited). For instance, if the arm-entering sequence for the 13 entries was 1241413344321, then the length of first patrolling is 7, because initial exploration was completed with entry into arm 3 on visit 7. The more visits a patrolling episode takes, the less efficient is exploration. 4. The total number of patrolling episodes made by an animal during the test. In the example above, this would be two, since the second patrolling episode was completed on the 13th trial. The more patrolling episodes made, the more efficient is exploration. The variables 3 and 4 highly correlate with open-field exploratory activity (Salimov et al., 1995c). 5. Immediate re-entry to the arm just visited previously. 6. Stereotyped visits—scored if the rat visits two arms in an alternating manner. In the example above, there is only one episode of four stereotyped visits (the 4141 pattern starting with the third entry). Masking white noise of 70 dB[A] was employed during the test. 2.3. Inescapable slip funnel test The slip funnel apparatus consisted of an upper cylindrical portion with vertical walls (8 cm high, 27.5 cm in diameter), a center funnel section (9.5 cm high) with walls sloping inward at an angle of approximately 408 from horizontal, and a lower cylindrical portion with vertical walls (4 cm high, 4.5 cm in diameter). Water (approximately 228C) filled the bottom cylinder and was replaced after each test. The depth of water was such that when standing immobile at the bottom, the hind legs of the animal would be immersed in the water. The slip funnel test started immediately after the crossmaze test. The animal was placed into the lower cylinder with its hind legs immersed in the water. The duration of the test was 3 min. The observer entered information directly into a computer, which was analyzed for time spent: 1. Standing or sitting in the water at the bottom of the funnel. 2. Climbing out of the water and sitting in a sprawling posture on sloping wall seen as a measure of avoidance behavior. 3. Attempts to jump out of the funnel interpreted as a measure of escape behavior. 2.4. Statistical analysis Statistical analysis was made with the help of the STATISTICA package. The methods used were t-test for depen-
R.M. Salimov et al. / Alcohol 20 (2000) 61–68
dent samples, and a two-way 3 3 2 ANOVA employing contrast procedure. The three-level variable, called “Group,” compares alcohol-naive, LD, and HD mice. The two-level variable, called “Treatment,” compares mice injected with vehicle and those injected with haloperidol. 3. Results 3.1. Experiment 1 3.1.1. Drinking behavior Subchronic haloperidol had differential effects on alcohol drinking during first 1.5 and remaining 22.5 h of first postdeprivation day. On the alcohol intake during first 1.5 h of renewed access to alcohol (Fig. 1, panel A), effects of all independent variables were significant. A two-way ANOVA yielded a significant Group [F(2,174) 5 4.72, p 5 0.01] and Treatment [F(1,174) 5 5.09, p 5 0.025] effects, as well as a significant interaction between the variables [F(2,174) 5 5.08, p 5 0.007]. In vehicle-treated animals (open columns), the ANOVA contrast procedure revealed higher consumption of alcohol by HD mice as compared to alcohol-naive or LD groups [F(1,174) 5 14.38, p 5 0.0002, and F(1,174) 5 14.9, p 5 0.0002, respectively]. The alcohol drinking by haloperidol HD mice (filled column) was significantly lower than that by vehicle HD mice [F(1,174) 5 15.24, p 5 0.0001].
Fig. 1. Means 6 SEM of alcohol intake in mice lacking (LD) and having (HD) the alcohol-deprivation effect and in alcohol-naive (N) mice. Before the drinking test, the animals received 14 daily i.p. injections of haloperidol (1 mg/kg) (filled columns) or vehicle (open columns) applied during alcohol deprivation. (A) Drinking during the first 1.5 h of renewed access to alcohol. (B) Intake during following 22.5 h. (C) The alcohol-deprivation effect (ADE) estimated as the difference between the first two values. Significant difference (p , 0.05, by ANOVA’s contrast): *, between vehicle and haloperidol groups; &, between HD and one of the LD or alcohol naive groups; #, significant difference (p , 0.05, t-test for dependent samples) between the first 1.5 and the last 22.5 h of the test.
On the alcohol intake during last 22.5 h of renewed access to alcohol (Fig. 1, panel B), a two-way ANOVA did not reveal significant effects for Group, Treatment, or interaction between the variables. The ANOVA contrast procedure, however, showed that difference in the alcohol drinking between haloperidol and vehicle HD mice approaches significance level [F(1,174) 5 3.98, p 5 0.048]. A t-test for dependent samples showed that alcohol consumption by HD mice during last 22.5 h of renewed access to alcohol was lower than during the first 1.5 h after deprivation both in vehicle [t(29) 5 2.76, p 5 0.01] and haloperidol [t(29) 5 3.45, p 5 0.002] groups. On the measure of ADE used (Fig. 1, panel C), a twoway ANOVA yielded a significant Group effect [F(2,174) 5 7.05, p 5 0.001] and a significant interaction between Group and Treatment variables [F(2,174) 5 4.12, p 5 0.018]. Among control groups treated with vehicle only, the ANOVA contrast procedure revealed a significant difference in this measure between HD mice and both the alcohol-naive [F(1,174) 5 15.34, p 5 0.0001] and the LD groups [F(1,174) 5 17.47, p 5 0.00005]. The ADE was significantly lower in the haloperidol HD group than in vehicle HD group [F(1,174) 5 11.11, p 5 0.001]. There was no significant change in water intake among the groups. 3.2.2. Behavior in the cross-maze and slip funnel tests Results of exploratory cross-maze test are presented in Table 1. On the total time spent in the center of the maze, a two-way ANOVA yielded a significant effect of Treatment only [F(1,174) 5 6.67, p 5 0.011] indicating a general increase in the measure after subchronic haloperidol. For the time spent inside arms, a two-way ANOVA also revealed a significant effect of Treatment only [F(1,174) 5 33.48, p , 0.000001]. Nevertheless, alcohol-naive mice spent more time in arms than did LD and HD mice taken together, [F(1,174) 5 6.37, p 5 0.012]. On the number of immediate reentries, a two-way ANOVA did not yield a significant Group or Treatment effect [F(2,174) 5 2.51, p 5 0.084, and F(1,174) 5 2.07, p 5 0.152, respectively]. However, the Group by Treatment interaction on the measure was significant [F(2,174) 5 3.09, p 5 0.048]. In HD mice, the number of immediate reentries was greater for the haloperidol than for the vehicle condition [F(1,174) 5 5.12, p 5 0.025]. Among the haloperidol groups, HD mice had a greater number of immediate reentries than did alcohol-naive or LD mice [F(1,174) 5 4.15, p 5 0.043, and F(1,174) 5 6.2, p 5 0.014, respectively]. The remaining measures of exploratory behavior did not show a significant difference between the groups. Results of slip funnel test are shown in Table 2. On the total time spent climbing out of the water and sitting in sprawling posture on a sloping wall, a two-way ANOVA yielded a significant effect of Treatment only [F(1,174) 5 5.02, p 5 0.026] indicating a general increase in this behavior after subchronic haloperidol. For the time spent attempt-
R.M. Salimov et al. / Alcohol 20 (2000) 61–68
Table 1 Meaures from exploratory cross-maze test performed in mice subchronically treated with vehicle or haloperidol Vehicle
Group of Animal
Number of animals Time before the 1st visit to an arm (sec) Total time in central compartment (sec) Total time in arms (sec) Number of visits on first patrolling Number of patrolling episodes Number of immediate re-entries Number of stereotyped visits
30 12.3 6 1.9 85.5 6 7.7 163.0 6 7.0 5.6 6 0.3 2.6 6 0.1 0.1 6 0.1 4.4 6 0.5
30 11.7 6 2.0 96.2 6 14.4 169.0 6 11.2 5.7 6 0.3 2.4 6 0.1 0.4 6 0.1 4.3 6 0.5
30 14.8 6 1.9 79.4 6 7.0 160.7 6 14.5 5.7 6 0.4 2.5 6 0.2 0.3 6 0.1 4.8 6 0.5
30 12.8 6 1.6 103.3a 6 10.7 265.8a 6 18.4 4.9 6 0.2 2.5 6 0.1 0.3 6 0.1 3.9 6 0.5
16.3 6 2.3 114.8a 6 10.1 212.0a b 6 16.2 5.6 6 0.4 2.4 6 0.1 0.3 6 0.1 5.6 6 0.5
17.5 6 1.9 109.1a 6 11.0 227.1a b 6 18.9 5.9 6 0.4 2.5 6 0.2 0.6a b c 6 0.1 4.5 6 0.6
Means (6 SEM) of cross-maze measures a day after 13th i.p. injection of vehicle or haloperidol (1 mg/kg) in mice lacking (LD), and having (HD) the alcohol-deprivation effect and in alcohol-naive (N) mice. Significant difference (p , 0.05) revealed by ANOVA’s contrast procedure. a Between vehicle and haloperidol groups. b Between alcohol naive and one of the LD or HD group. c Between LD and HD groups.
On the alcohol intake during last 22.5 h of renewed access to alcohol (Fig. 2, panel B), a two-way ANOVA did not reveal a significant effect of Group, Treatment, or interaction between the variables. A t-test for dependent samples showed that alcohol consumption by HD mice during last 22.5 h of renewed access was lower than during the first 1.5 h both in vehicle [t(19) 5 4.83, p 5 0.0001] and haloperidol [t(19) 5 5.61, p 5 0.00002] conditions. On the measure of ADE used (Fig. 2, panel C), a twoway ANOVA yielded a significant Group effect only [F(2,114) 5 27.67, p , 0.000001] indicating a difference between HD mice and both alcohol-naive or LD mice. The ADE did not differ significantly between haloperidol and vehicle conditions. Water intake did not vary systematically among the groups.
ing to jump out of the funnel, a two-way ANOVA revealed a significant effect of Group only [F(1,174) 5 3.25, p , 0.041]. The ANOVA contrast procedure revealed a significant difference in this behavior between HD mice and both the alcohol-naive [F(1,174) 5 5.434, p 5 0.021] and the LD groups [F(1,174) 5 6.47, p 5 0.012]. The measure, however, was significantly lower in the haloperidol HD group than in vehicle HD group [F(1,174) 5 5.07, p 5 0.026]. The total time standing in the water at the bottom of the funnel did not show any significant difference between the groups. 3.2. Experiment 2 There was no significant difference in alcohol drinking between vehicle and haloperidol mice after a single administration of haloperidol. On the alcohol intake during first 1.5 h of renewed access to alcohol (Fig. 2, panel A), a two-way ANOVA yielded a significant Group effect only [F(2,114) 5 34.65, p , 0.000001] indicating higher consumption of alcohol by HD mice than by alcohol-naive [F(1,114) 5 14.38, p 5 0.0002] or LD mice [F(1,114) 5 14.9, p 5 0.0002].
4. Discussion The major finding in the present investigation is attenuation of the ADE in HD mice by prior a series of haloperidol injections ending 24 h before renewed access to alcohol. Although the alcohol intake decreased both during first 1.5
Table 2 Measures from slip funnel test performed in mice subchronically treated with vehicle or haloperidol Vehicle
Group of animal
Number of animals Total time of standing in the water at the bottom of the funnel (sec) Total time of climbing out of the water and sitting in sprawling posture on a sloping wall (sec) Total time of attempts to jump out of the funnel (sec)
30 171.1 6 3.2
30 173.66 2.0
30 165.5 6 6.6
30 159.5 6 9.5
30 165.6 6 7.8
30 155.8 6 9.3
6.9 6 2.7
4.4 6 1.5
9.2 6 4.8
20.1a 6 9.4
13.8a 6 7.6
22.4a 6 8.8
1.1 6 0.8
0.8 6 0.3
4.0a b 6 1.9
0.4 6 0.2
0.3 6 0.2
1.2 6 0.6
Means (6 SEM) of slip funnel measures a day after 13th i.p. injection of vehicle or haloperidol (1 mg/kg) in mice lacking (LD), and having (HD) the alcohol-deprivation effect and in alcohol-naive (N) mice. Significant difference (p , 0.05) revealed by ANOVA’s contrast procedure. a Between vehicle and haloperidol groups. b Between HD and one of the alcohol naive or LD group.
R.M. Salimov et al. / Alcohol 20 (2000) 61–68
Fig. 2. Means 6 SEM of alcohol intake in mice lacking (LD) and having (HD) the alcohol-deprivation effect and in alcohol-naive (N) mice after 14 days of alcohol deprivation. Before the drinking test, the animals received 14 daily i.p. injection of vehicle (open columns) or 13 daily i.p. administration of vehicle followed by single injection of haloperidol (1 mg/kg) (filled columns). Symbols are the same as in Fig. 1.
and last 22.5 h of first postdeprivation day, the effect of the treatment was more prominent during initial 1.5 h of renewed access to alcohol indicating a 79% decline in the ADE after subchronic haloperidol (Fig. 1). A day after a single injection of haloperidol, however, there was no significant decrease in drinking of alcohol by HD mice. Among alcohol-naive and LD mice, haloperidol administration did not change the alcohol intake significantly. No systematic variation in water intake was found among the groups. The results of the present study are in accord with those of other investigations employing limited access paradigm. Although haloperidol applied in a dose of 1 mg/kg 30 min prior to the drinking test reduces both the alcohol and water intake, the measures return to their pre-injection levels a day after administration of the drug (Russell et al., 1996). During activation of dopaminergic neurotransmission caused by action of D2 agonists (quinpirole, apomorphine and SDZ205,152), both luck of the effect of the drugs on water or saccharin drinking and a decrease in alcohol intake have been observed (Dyr et al., 1993; Rassnick et al., 1993a; Russell, 1996). The latter effect was most prominent during the first postdeprivation hour of the limited access session. The reduction in alcohol intake during the first 1.5 h of renewed access to alcohol was also seen after administration of a MAO-inhibiting drug pirlindol, while the drug did not change the water consumption (Salimov & Viglinskaia, 1990). Although most of the cross maze variables, including those reflecting exploratory efficacy, did not change after subchronic haloperidol, there was a slight decrease in animal motility seen in drug groups. The total time in central
compartment was diminished at the same extend in all drug groups. The reduction in the total time in arms, nonetheless, was less prominent in LD and HD mice, as compared with alcohol-naive mice, suggesting lower susceptibility of this behavior in alcohol-experienced animals to the haloperidol treatment. An increase in climbing out of the water in the slip funnel test observed in all drug groups shows lack of general impairment of major motor skills a day after subchronic haloperidol. Attempts to escape out of the funnel were more prominent in the vehicle HD group as compared with the remaining control groups. The variable has been recently proposed as predictor of high alcohol drinking in the mice (Salimov, 1999; Salimov et al., 1995a) and P rats (Salimov et al., 1996a; Salimov et al., 1996b). Insofar as pattern of these behavioral changes among the groups differs from that observed for the ADE, it seems unlikely that they are related to the reduction in the ADE seen in HD mice. The results of both the cross maze and slip funnel tests are also in accord to previous studies describing a decrease in exploratory activity as well as an increase in avoidance and climbing behavior as behavioral signs of functional supersensitivity of dopamine receptors after subchronic haloperidol (Kuruvilla et al., 1982; Rosic & Overstreet, 1982; Thornburg & Moore, 1975). The results clearly show that subchronic haloperidol is capable of reducing volitional consumption of alcohol during first hours of renewed access, a variable considered as a measure of loss of control (Wolffgramm & Heyne, 1995) or relapse (Kornet et al., 1991; McKinzie et al., 1996) after imposed abstinence. In agreement with previous studies employing manipulations with serotonergic (McBride et al., 1995; McKinzie et al., 1996) and glutamatergic (Salimov & Salimova, 1993a) drugs, the present results also indicate a differential sensitivity to pharmacological agents of alcohol drinking during the initial phase of the ADE and during subsequent period of access to alcohol. This distinction is also consistent with the idea that dopamine plays a role in the attention to drinking of alcohol and the perseveration of the response. In addition to previous works demonstrating association of the ADE with glutamate (Salimov & Salimova, 1993b) and opiate (Salimov et al., 1993; Sinclair & Bender, 1978) neurotransmitter systems, the present data, combined with recent neurochemical studies (Wolffgramm & Heyne, 1995), hint at involvement of D2 dopamine neurotransmission into regulation of the ADE. Although much work is needed before clinical application can be considered, it might nevertheless be mentioned that the present results suggest the possibility that subchronic haloperidol might be useful for correction of an excessive drinking of alcohol. References Amit, Z., & Brown, Z. W. (1982). Actions of drugs of abuse on brain reward systems: a reconsideration with specific attention to alcohol. Pharmacol Biochem Behav 17, 233–238.
R.M. Salimov et al. / Alcohol 20 (2000) 61–68 Banish, T. G., Maisto, S. A., Cooper, A. M., & Sobell, M. B. (1981). Effects of voluntary short-term abstinence from alcohol on subsequent drinking patterns of college students. J Stud Alcohol 42, 1013–1020. Brown, Z. W., Gill, K., Abitbol, M., & Amit, Z. (1982). Lack of effect of dopamine receptor blockade on voluntary ethanol consumption in rats. Behav Neural Biol 36, 291–294. Daoust, M., Moore, N., Saligaut, C., Lhuintre, J. P., Chretien, P., & Boismare, F. (1986). Striatal dopamine does not appear involved in the voluntary intake of ethanol by rats. Alcohol 3, 15–17. Daoust, M., Saligaut, C., Chadelaud, M., Chretien, P., Moore, N., & Boismare, F. (1984). Attenuation by antidepressant drugs of alcohol intake in rats. Alcohol 1, 379–383. DiBattista, D. (1991). Examination of the negative alcohol-deprivation effect in the golden hamster (Mesocricetus auratus). Alcohol 8, 337–343. Dyr, W., McBride, W. J., Lumeng, L., Li, T.-K., & Murphy, J. M. (1993). Effects of D1 and D2 dopamine receptor agents on ethanol consumption in the high-alcohol-drinking (HAD) line of rats. Alcohol 10, 207–212. Eravci, M., Grosspietsch, T., Pinna, G., Schulz, O., Kley, S., Bachmann, M., Wolffgramm, J., Gotz, E., Heyne, A., Meinhold, H., & Baumgartner, A. (1997). Dopamine receptor gene expression in an animal model of ‘behavioral dependence’ on ethanol. Brain Res Mol Brain Res 50, 221–229. Fuchs, V., Burbes, E., & Coper, H. (1984). The influence of haloperidol and aminooxyacetic acid on etonitazene, alcohol, diazepam and barbital consumption. Drug Alcohol Depend 14, 179–186. Fuchs, V., Coper, H., & Rommelspacher, H. (1987). The effect of ethanol and haloperidol on dopamine receptor (D2) density. Neuropharmacol 26, 1231–1233. George, S. R., Fan, T., Ng, G. Y., Jung, S. Y., O’Dowd, B. F., & Naranjo, C. A. (1995). Low endogenous dopamine function in brain predisposes to high alcohol preference and consumption: reversal by increasing synaptic dopamine. J Pharmacol Exp Ther 273, 373–379. Goodwin, F. L., Koechling, U. M., Smith, B. R., & Amit, Z. (1996). Lack of effect of dopamine D2 blockade on ethanol intake in selected and unselected strains of rats. Alcohol 13, 273–279. Goss, J. R., Kelly, A. B., Johnson, S. A., & Morgan, D. G. (1991). Haloperidol treatment increases D2 dopamine receptor protein independently of RNA levels in mice. Life Sci 48, 1015–1022. Kiianmaa, K., Andersson, K., & Fuxe, K. (1979). On the role of ascending dopamine systems in the control of voluntary ethanol intake and ethanol intoxication. Pharmacol Biochem Behav 10, 603–608. Kornet, M., Goosen, C., & Van Ree, J. M. (1990). The effect of interrupted alcohol supply on spontaneous alcohol consumption by rhesus monkey. Alcohol Alcohol 25, 407–412. Kornet, M., Goosen, C., & Van Ree, J. M. (1991). Effect of naltrexone on alcohol consumption during chronic alcohol drinking and after a period of imposed abstinence in free-choice drinking rhesus monkeys. Psychopharmacol 104, 367–376. Kuruvilla, A., Fung, Y. K., & Uretsky, N. J. (1982). Behavioral and biochemical changes caused by muscimol in mice withdrawn from haloperidol administration. Neuropharmacol 21, 891–897. LeMagnen, J. (1960). Study of some factors related to alteration of voluntary consumption of ethyl alcohol in rat. J Physiol 52, 873–884. Levy, A. D., Murphy, J. M., McBride, W. J., Lumeng, L., Li, T.-K. (1991). Microinjection of sulpiride into the nucleus accumbens increases ethanol drinking in alcohol-preferring (P) rats. Alcohol Alcohol (Suppl.) 26, 417–420. MacLennan, A. J., Atmadja, S., Lee, N., & Fibiger, H. C. (1988) Chronic haloperidol administration increases the density of D2 dopamine receptors in the medial prefrontal cortex of the rat. Psychopharmacol 95, 255–257. McBride, W. J., Chernet, E., Dyr, W., Lumeng, L., Li, T.-K. (1993). Densities of dopamine D2 receptors are reduced in CNS regions of alcoholpreferring P rats. Alcohol 10, 387–390. McBride, W. J., Cox, R., Eha, R., McKinzie, D. L., Lumeng, L., Li, T.-K., & Murphy, J. M. (1995). Possible involvement of 5-HT3 receptors in the anticipatory behavior of P rats for alcohol. Alcohol Clin Exp Res (Suppl.) 19, 14A.
McBride, W. J., Murphy, J. M., Lumeng, L., & Li, T.-K. (1990). Serotonin, dopamine and GABA involvement in alcohol drinking of selectively bred rats. Alcohol 7, 199–205. McKinzie, D. L., Eha, R., McBride, W. J., Murphy, J. M., Lumeng, L., & Li, T.-K. (1996). Evidence for neuroadaptive changes that occur during abstinence and promote alcohol relapse. Alcohol Clin Exp Res (Suppl.) 20, 15A. Myers, R. D. (1990). Anatomical “circuitry” in the brain mediating alcohol drinking revealed by THP-reactive sites in the limbic system. Alcohol 7, 449–459. Ng, G. Y., & George, S. R. (1994). Dopamine receptor agonist reduces ethanol self-administration in the ethanol-preferring C57BL/6J inbred mouse. Eur J Pharmacol 269, 365–374. Ng, G. Y., O’Dowd, B. F., & George, S. R. (1994). Genotypic differences in brain dopamine receptor function in the DBA/2J and C57BL/6J inbred mouse strains. Eur J Pharmacol 269, 349–364. Pfeffer, A. O., & Samson, H. H. (1986). Effect of pimozide on home cage ethanol drinking in the rat: dependence on drinking session length. Drug Alcohol Depend 17, 47–55. Quarfordt, S. D., Kalmus, G. W., & Myers, R. D. (1991). Ethanol drinking following 6-OHDA lesions of nucleus accumbens and tuberculum olfactorium of the rat. Alcohol 8, 211–217. Rankin, H., Hodgson, R., & Stockwell, T. (1979). The concept of craving and its measurement. Behav Res Ther 17, 389–396. Rassnick, S., Pulvirenti, L., & Koob, G. F. (1992). Oral ethanol self-administration in rats is reduced by the administration of dopamine and glutamate receptor antagonists into the nucleus accumbens. Psychopharmacol 109, 92–98. Rassnick, S., Pulvirenti, L., & Koob, G. F. (1993a). SDZ-205,152, a novel dopamine receptor agonist, reduces oral ethanol self-administration in rats. Alcohol 10, 127–132. Rassnick, S., Stinus, L., & Koob, G. F. (1993b). The effects of 6-hydroxydopamine lesions of the nucleus accumbens and the mesolimbic dopamine system on oral self-administration of ethanol in the rat. Brain Res 623, 16–24. Richardson, J. S., & Novakovski, D. M. (1978). Brain monoamines and free choice ethanol consumption in rats. Drug Alcohol Depend 3, 253– 264. Rosic, N., & Overstreet, D. H. (1982). Facilitation of active avoidance responding following chronic haloperidol treatment in rats. Psychopharmacol 78, 135–136. Russell, R. N., McBride, W. J., Lumeng, L., Li, T.-K., & Murphy, J. M. (1996). Apomorphine and 7-OH DPAT reduce ethanol intake of P and HAD rats. Alcohol 13, 515–519. Salimov, R. M. (1988). Measurement of the way choice order during exploratory behavior in mice. Zh Vyssh Nerv Deiat Im I P Pavlova 28, 569–570. Salimov, R. M. (1999). Different behavioral patterns related to alcohol use in rodents: a factor analysis. Alcohol 17, 157–162. Salimov, R., Salimova, N., Klodt, P., & Maisky, A. (1993). Interaction between alcohol deprivation and morphine withdrawal in mice. Drug Alcohol Depend 34, 59–66. Salimov, R., Salimova, N., Ratkin, A., Shvets, L., & Maisky, A. (1995a). Genetic control of alcohol deprivation effect in congenic mice. Alcohol 12, 469–474. Salimov, R., Salimova, N., Shvets, L., & Shvets, N. (1995b). Effects of chronic piracetam on age-related changes of cross-maze exploration in mice. Pharmacol Biochem Behav 52, 637–640. Salimov, R. M., McBride, W. J., McKinzie, D. L., Lumeng, L., & Li, T.-K. (1996a). Effects of ethanol consumption by adolescent alcohol-preferring P rats on subsequent behavioral performance in the cross-maze and slip funnel tests. Alcohol 13, 297–300. Salimov, R. M., McBride, W. J., Sinclair, J. D., Lumeng, L., & Li, T.-K. (1996b). Performance in the cross-maze and slip funnel tests of four pairs of rat lines selectively bred for divergent alcohol drinking behavior. Addict Biol 1, 273–280. Salimov, R. M., Poletaeva, I. I., Kovalev, G. I., Salimova, N. B., & Gainet-
R.M. Salimov et al. / Alcohol 20 (2000) 61–68
dinov, R. R. (1995c). Interstrain differences in extrapolation capacity and exploration of a cruciform maze correlate with various indices of monoamine metabolism in the brain. Zh Vyssh Nerv Deiat Im I P Pavlova 45, 914–924. Salimov, R. M., & Salimova, N. B. (1993a). L-glutamate abolishes differential responses to alcohol deprivation in mice. Alcohol 10, 251–257. Salimov, R. M., & Salimova, N. B. (1993b). The alcohol-deprivation effect in hybrid mice. Drug Alcohol Depend 32, 187–191. Salimov, R. M., & Viglinskaia, I. V. (1990). Evaluation of accelerated development of stable alcoholic motivation in rats for studying potential alcohol deterrents. Biull Eksp Biol Med 109, 364–366. Sanders, B., Collins, A. C., Petersen, D. R., & Fish, B. S. (1977). Effects of three monoamine oxidase inhibitors on ethanol preference in mice. Pharmacol Biochem Behav 6, 319–324. Silvestre, J. S., O’Neill, M. F., Fernandez, A. G., & Palacios, J. M. (1996). Effects of a range of dopamine receptor agonists and antagonists on ethanol intake in the rat. Eur J Pharmacol 318, 257–265. Sinclair, J. D. (1971). The alcohol-deprivation effect in monkeys. Psychonom Sci 25, 21–22. Sinclair, J. D., Adkins, J., & Walker, S. (1973). Morphine-induced suppression of voluntary alcohol drinking in rats. Nature 246, 425–427. Sinclair, J. D., & Bender, D. O. (1978). Compensatory behaviors: suggestion for a common basis from deficits in hamsters. Life Sci 22, 1407– 1412.
Sinclair, J. D., & Li, T.-K. (1989). Long and short alcohol deprivation: effects on AA and P alcohol-preferring rats. Alcohol 6, 505–509. Sinclair, J. D., & Senter, R. J. (1967). Increased preference for ethanol in rats following alcohol deprivation. Psychonom Sci 8, 11–12. Sinclair, J. D., & Senter, R. J. (1968). Development of an alcohol-deprivation effect in rat. Q J Stud Alcohol 29, 863–867. Stanishevskaia, A. V., Kogan, B. M., Khristoliubova, N. A., & Anokhina, I. P. (1985). Effect of bromocryptin on the alcohol consumption and catecholamine level in the brain of rats undergoing long-term alcoholization. Farmakol Toksikol 48, 88–91. Stefanini, E., Frau, M., Garau, M. G., Garau, B., Fadda, F., & Gessa, G. L. (1992). Alcohol-preferring rats have fewer dopamine D2 receptors in the limbic system. Alcohol Alcohol 27, 127–130. Thornburg, J. E., & Moore, K. E. (1975). Supersensitivity to dopaminergic agonists induced by haloperidol. Natl Inst Drug Abuse Res Monogr Ser 3, 23–28. Wise, R. A., & Bozarth, M. A. (1987). A psychomotor stimulant theory of addiction. Psychol Rev 94, 469–492. Wolffgramm, J., & Heyne, A. (1995). From controlled drug intake to loss of control: the irreversible development of drug addiction in the rat. Behav Brain Res 70, 77–94. Wolffgramm, J., Rommelspacher, H., & Buck, E. (1990): Ethanol reduces tolerance, sensitization, and up-regulation of D2- receptors after subchronic haloperidol. Pharmacol Biochem Behav 36, 907–914.