THE INSULIN ACTIVITY OF BOVINE AND OVINE BLOOD PLASMA

Abstract

SUMMARY The acid—ethanol extraction procedure described by Baird & Bornstein (1957) has been shown to extract from bovine and ovine blood plasma material having an insulin-like action in vitro in the rat diaphragm assay. The amounts of insulin activity extracted from plasma of non-pregnant cows and sheep generally indicated plasma insulin levels of from 100–500 μu./ml. plasma. Plasma insulin activity did not appear to be related to plasma glucose level in these animals. Insulin activities of 100 μu./ml. plasma, or less, were found in two cows soon after parturition, in some pregnant sheep bearing twins round about the time of parturition, in four acetonaemic cows and in three of six sheep with pregnancy toxaemia.