ON RAT SERUM AMYLASE I. STUDIES IN THE NORMAL AND THE ALLOXAN DIABETIC ANIMAL

Abstract

A dextrinogenic micromethod was used to establish serum amylase levels in adult male and female rats which were maintained on a standard laboratory diet. A highly significant difference was found to exist between the activities of the enzyme in the male and female rats. The effect of fasting, and of limiting food consumption, indicated a highly significant correlation between daily food intake and serum amylase levels. The polyphagia manifested by alloxan diabetic rats was not reflected in abnormally high amylase activity, as might be expected, but there was a departure from the normal response to the levels of food ingested each day. Oestradiol dipropionate and testosterone propionate were injected into normal male and female rats for seven days. Treatment with male hormone produced no significant variation in food consumption or serum amylase activity in either sex. Injections with oestradiol resulted in significantly lowered food intake in both sexes, but only in the case of males was there an accompanying fall in enzyme levels. On the basis of the experiments described in this paper it is seen that rat serum amylase consists of two fractions, and that the major portion may be considered to be of an adaptive nature. This adaptive portion appears to a large measure to be a reflection of the total daily food intake, which may be influenced by certain factors, such as sex hormones and alloxan diabetes.