INDUCTION AND COURSE OF PERMANENT DIABETES PRODUCED BY ANTERIOR PITUITARY EXTRACT

Abstract

Observations have been made upon the induction, course and nature of the permanent diabetes that occurred in 10 dogs after a series of intraperit. injs. of ant. pituitary extract (APE). The permanent phase was produced in 6 dogs after a period of 14-43 days of inj. of increasingly larger doses of APE. Inj. of smaller doses for mos. also produced a permanent diabetic state. In 2 dogs, the removal of a portion of the pancreas abolished resistance to the diabetogenic effect of APE. N retention was found during the inj. period when the glycosuria attributable to, protein sources was not severe. During the permanent phase of the diabetes (i.e., after stopping extract injs.) there was a progressive increase in glycosuria until 80-85% or more of the available dietary glucose was excreted. Insulin treatment inhibited the rate of progress of the diabetes. There was no evidence of an inhibition of insulin action such as that found during the period of APE injns. In 3 animals the diabetes became so severe that fasting urinary excretion of glucose and N was similar to that of untreated totally depancreatized dogs. Values for liver glycogen and fatty acids similar to those of depancreatized dogs occurred in these animals. The pancreas of the 8 dogs examined during the permanent phase exhibited atrophy of the islands of Langerhans as the predominant lesion. No evidence of the continued overactivity of the pituitary, adrenal or thyroid glands was found. These observations support the concept that the permanent phase of the diabetes is primarily due to a loss of function of the islands of Langerhans.