INSULIN RESPONSE TO GLUCAGON

INSULIN RESPONSE TO GLUCAGON

92 hyperosmolarity is primarily a consequence of the high blood-sugar level, but even hypersomolarity is not always a characteristic feature, though ...

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92

hyperosmolarity is primarily a consequence of the high blood-sugar level, but even hypersomolarity is not always a characteristic feature, though it may be severe (levels from 317 to more than 380 mosmoles per litre were reported.2 Thus three questions arise: (1) Is hyperosmolar coma " a useful term ? (2) Is the condition a new syndrome ? (3) If

The

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symptoms characteristic of diabetic coma are absent, and the signs of cardiovascular or renal failure are prominent, why should the condition not be termed cardiovascular or renal atypical diabetic coma, as has been suggested ?17-1Hyperosmolarity is a general characteristic of diabetic coma. Therefore the term is not suitable for differentiating comatose conditions; more, it may be misleading when prescribing the intravenous-fluid-therapy, since for this the electrolyte findings are of decisive importance. In so-called atypical coma, there is absence of the characteristic signs of diabetic coma, such as Kussmaul-type breathing, low carbon-dioxidebinding capacity, and acetonuria; and Hetényi 17 several decades ago reported on cases without acidosis-in his opinion, the absence of acidosis is characteristic of atypical coma. From the descriptions of Frerichs"8 and Naunyn,19 the atypical form termed cardiovascular coma, characterised by collapse and rapidly developing cardiac failure, has been differentiated from typical diabetic coma. As in the casereports I have cited above, arterial blood-pressure is low, and Kussmaul-type breathing and cerebral symptoms are absent. The term renal coma to designate the other atypical form, which seems to date back to Warburg, is self-explanatory. To sum up, I would suggest terming the condition at issue cardiovascular (or renal) atypical diabetic coma, the more so since this would give a clearer indication of the kind of treatment required than the now-usual designation " hyperosmolar " coma. Department of Paediatrics, University Medical School, Budapest.

1st

L. BARTA.

INSULIN RESPONSE TO GLUCAGON

SIR,-We were interested in the observations of Dr. Weber last week (p. 49) on the failure of a fasting child to show a rise in plasma-insulin after intravenous glucagon, whereas 3 hours after a meal on the same day there was a striking response. Our observations (to be published) on the insulinreleasing activity (I.R.A.) of oral tryptophan show a similar PLASMA-INSULIN LEVELS IN FASTING AND NON-FASTING

SUBJECTS

AFTER

A STANDARD ORAL LOAD OF TRYPTOPHAN

of tryptophan.

Bristol.

B. AJDUKIEWICZ P. M. KEANE J. PEARSON A. E. READ P. R. SALMON.

17. Hetényi, G. Az Anyagcsere-betegségek Kór- es Gyógytana. 1933. 18. Frerichs, von Th. Über den Diabetes. Berlin, 1884. 19. Naunyn, B. Der Diabetes Mellitus. Vienna, 1906.

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(no.=89, s.D.=4°48)

and 137-62

(no.=98, S.D.=4.34)-i.e.,

standard deviations below the average of Dr. Rimoin and his colleagues’ female sample. This may be due to a sampling error, the numbers of Dr. Rimoin and his colleagues’ subjects being very small, but we must take into account another two

possible explanation. "

There are many populations called "pygmies because, from the European point of view, they are very short. Nevertheless, they differ markedly from pygmies in the strict sense. (The most obvious difference is that these populations are much taller.) Pygmies in the strict sense such as the Aka, the Basua, or the Efe, are forest dwellers, genetically isolated from surrounding Negro populations, but the converse is not true. Prof. H. V. Vallois has told me that in many areas pygmy women sometimes leave the forest in order to marry Negro farmers, such a marriage appearing to them as a social success. But Negro women never marry pygmies, whose life is considered as very hard and primitive. This one-way exogamy has some important consequences: the typical pygmies keep their very short stature, whereas the body-height of some Negro groups has been shortened by intermarriage with pygmy women. Of course, these hybrid populations have inherited some other pygmoid characters also. In practice, it may be difficult to know the taxonomic position of some groups, much shorter than Negroes, but obviously taller than the shortest among the pygmies. It would be interesting to know the H.G.H. level of the latter, because they seem to have preserved the characteristics of a It would also be illuminating to see true pygmy isolate. whether there is at least a low correlation between individual H.G.H. levels and individual body-heights. Laboratoire d’Anthropologie Physique, Ecole des Hautes Etudes, and Laboratoire de Biométrie Humaine, Centre National de la Recherche Scientifique, Paris.

pattern (see accompanying table). In 6 fasting subjects no increment in plasma-i.R.A. was noted, whereas there was a striking rise in 13 patients studied 2 hours after a meal. This increase was highly significant at 30 minutes (t=3-1). Our results and those of Dr. Weber suggest that glucagon release may be of importance in the insulin-releasing action

Departments of Medicine and Pathology, Bristol Royal Infirmary,

GROWTH HORMONE IN AFRICAN PYGMIES SIR,-As a physiologically minded rather than a physical " anthropologist, I am interested in the paper of Dr. Rimoin and his colleagues (Sept. 9, p. 523). They show that in African pygmies human growth hormone (H.G.H.) level is not lower than in other human beings. I am puzzled, however, by the average statures of the samples given: 151-85 cm. for 15 males and 146-20 cm. for 7 females. According to pygmy standards, these men and women should be considered almost as giants. Average statures in the two samples of undoubtedly pygmy populations in the Ituri forests (formerly Belgian Congo) are, for male, 144-31 cm. (no. = 115, s.D.=5’58) and 144’09 (no.=96, S.D.=5.00)-i.e., more than a standard deviation below the average of Dr. Rimoin and his colleagues’ male pygmies. The averages of two typical pygmy female samples are 136-94 cm.

Budapest,

E. SCHREIDER.

SIR,-The important paper by Dr. Rimoin and his coauthors poses some questions. When Western men first penetrated into Central Africa, pygmies were found throughout the rain forests of the Congo and in greatest number north and east of the Congo river. The social organisation of each pigmy tribe was usually based on dependence on and mutual assistance with a tribe of normalsized Negroes who practised a primitive form of agriculture. Schweinfurth,l exactly one hundred years ago, was the first explorer to place the existence of the pygmies beyond doubt. In his account of his travels in the country of the relatively advanced Monbuttoo Negroes, he wrote of their client tribe of Akka dwarfs: " I never saw an instance in which the height materially exceeded 4 ft. 10 in. (147-5 cm.) ". This compares with the mean height of 151-85 cm. for fifteen males in the series reported by Dr. Rimoin and his co-authors. Schweinfurth had no doubt that a good deal of interbreeding occurred, and mentions that the Akka resembled the majority of the Monbuttoo in having brown hair, together with a complexion of reddish tone. The only pygmy whose exact height he 1.

Schweinfurth, G. The Heart

of Africa.

London, 1873.