Bernard B. Longwell

Effect of Alloxan Diabetes on Fertility and Gestation in the Rat.

Summary Rats were made diabetic with alloxan and their ability to reproduce was studied under various conditions. The following observations were made: (1) the estrous cycle ceased in diabetic females and was restored by the administration of insulin; (2) 4 of 13 untreated diabetic animals, which were bred before the estrous cycle ceased, produced litters; (3) insulin treated diabetic animals reproduced in spite of a continuing hyperglycemia; (4) transient hyperglycemia did not interfere with reproduction and (5) diabetes in the mother did not result in hyperglycemia in the offspring in the few animals tested.

Related Effects of Acute Exposure to Cold and Fasting on Free Fatty Acid Release by Adipose Tissue.

Summary Rats deprived of food at the beginning of the experiment were exposed to a cold environment at 3-5 °C for periods varying from 4 to 30 hours. The release of FFA by epididymal adipose tissue in vitro was compared to that from animals maintained at room temperature of 25°C. FFA was released in significantly greater amounts by the tissue of the animals exposed to cold until the fast had progressed for 30 hours, at which time there was no difference between the two groups. Following a fast of 18 hours, the adipose tissue from the cold-exposed group and from the warm room group responded similarly to epinephrine and norepinephrine.

EFFECT OF FASTING OR FEEDING ON RELEASE OF FREE FATTY ACID BY THE ADIPOSE TISSUE OF THE COLD-ACCLIMATED RAT.

Summary White rats were exposed to a temperature of 3-5°C for periods varying from 24 hours to 35 days. Adipose tissue from animals so exposed from 1 to 20 days or for 35 days produced 3 to 4 times more FFA than did tissue from animals maintained at room temperature. However, if the animals were fasted before the tissue was removed, these differences virtually disappeared. It is evident that studies of participation of the adipose tissue in the adjustment of the rat to a cold environment should be interpreted relative to the nutritional state of the animal at the time the studies are made.

The Effects of Adrenocorticotrophin Hormone and Metyrapone on the Excretion of Urinary Steroids by Beagle Dogs Burdened with Strontium-90

Urinary 17-ketogenic steroids, 17-ketosteroids, and 17-hydroxycorticosteroids were measured in a group of Beagle dogs at various times after inhalation of

ESTROGENS WITH OXYGEN IN RING B III. 6-KETO-α-ESTRADIOL

{}^{90}{\rm SrCl}{}_{2}

EXTRACTION OF CORTICOSTEROIDS FROM ADRENAL VEIN BLOOD OF RATS AND RABBITS1

aerosols. In another group of dogs, urinary 17-ketogenic steroids and 17-ketosteroids were measured in dogs twenty-six months after the intravenous administration of90 Sr. Adrenocorticotrophin (ACTH) and metyrapone were used in this latter group as initiators of provocative tests, as aids in assessing adrenal and hypothamic-pituitary function. A statistically significant difference was found between sexes, where female animals excreted more 17-ketogenic steroids than male animals, and male animals excreted more 17-ketosteroids than female animals. A large amount of variability occurred among dogs and among groups. No statistically significant difference in urinary steroid levels in control dogs and dogs that had received90 Sr was noted before or after administration of ACTH or metyrapone.