Modification of fat and carbohydrate metabolism by neurohypophyseal hormones. III. Effect of oxytocin on non-esterified fatty acid, glucose, triglyceride and cholesterol levels in rat serum.

The authors determined the effect of s.c. injected oxytocin on serum non-esterified fatty acid, triglyceride, cholesterol and glucose levels in fed and fasting rats of both sexes, in doses of 2.5 and 5 I.U./kg. No changes in non-esterified fatty acid levels were found in fasting animals of either sex. In fed males, non-esterified fatty acid levels rose abruptly after both doses; in fed females they fell after the larger dose. In fed animals of both sexes, the smaller dose of oxytocin produced a decrease, and the larger dose an increase, in triglyceride levels. In fasting females, triglyceride levels fell after both doses; in fasting males a temporary increase was found after the larger dose. In the great majority of cases cholesterol levels displayed a tendency to fall, in both males and females. In the case of glucose, a transient increase was recorded in fed animals of both sexes after the smaller dose and a decrease in males after the larger dose. In fasting animals, glucose levels temporarily rose in every case.