PARS GLANDULARIS AND METABOLISM 



after the injection of 1-5 (?) units of insulin into normal fast- 

 ing rats, there appeared to be no other change except a fall 

 in the concentration of sugar in the blood from 90 mg. per 

 cent to 60-70 mg, per cent, the injection of 0.05 unit into 

 fasting hypophysectomized rats depressed the level of the 

 blood sugar to 30-40 mg. per cent, with which were asso- 

 ciated myasthenia, rapid, shallow respiration, and coma often 

 with convulsions. The injection of i cc. of 20 per cent glucose 

 15 minutes after the administration of insulin maintained the 

 level of the blood sugar above normal; the rats appeared 

 normal and did not lapse into coma — yet they usually died 

 within about 5 hours. Smith and others (1936) tested the 

 insulin-sensitivity of normal, partially hypophysectomized, 

 and completely hypophysectomized monkeys which first 

 underwent a fast of 16 hours. Thirty minutes after the in- 

 jection of 0.06 unit of insulin per kilogram body-weight, the 

 following changes were observed in the concentration of 

 sugar in the blood of the heart (the figures refer to milligrams 

 per cent; the pre-injection concentration is given first): nor- 

 mal, 115 then 99; partially hypophysectomized, 78 then 66; 

 completely hypophysectomized, 57 then 37. According to 

 Crandall and Cherry (1937), who performed their experi- 

 ments in dogs, either hypophysectomy or denervation of the 

 adrenals — i.e., excision of one adrenal and splanchnotomy on 

 the other side — prevents an increased liberation of glucose 

 from the liver after the injection of insulin. The authors 

 secured blood from the hepatic and portal veins and arterial 

 blood without recourse to anesthesia. 



The effect of diet on the response of normal and hypophy- 

 sectomized dogs to insulin was studied by Heinbecker, 

 Somogyi, and Weichselbaum (1937). In operated, but not 

 in normal, dogs the response to insulin was uniformly better 

 if the animals were fed a high-carbohydrate, low-fat diet in 

 comparison with a diet low in carbohydrate and high in fat. 

 On the other hand, Himsworth and Scott found that normal 

 rabbits, on a diet low in carbohydrate, exhibited a disturbed 



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