Storage of acidophilic granules in the pituitary in experimental hyperglycaemia

Abstract

Pituitaries of Syrian hamsters with and without chronic hyperglycaemia were studied with morphometric and karyometric methods. The hyperglycaemic state was induced by low doses of alloxan, and maintained for 25 to 37 days. It had been potentiated in one group by a resection of at least 50% of pancreatic tissue prior to alloxan administration. A marked rise in the volume of the acidophils was found (p< 0.005). On the other hand, the karyometric studies revealed a definite diminution of the mean nuclear area of the acidophils in the diabetic animals, indicating decreased activity. The combination of an increase in mass of acidophils and a decrease in their nuclear activity supports the theory of an increased storage rather than hypersecretion of a hormone. The hormone which was stored in the acidophils is probably identical with growth hormone. If we consider the role of this hormone in carbohydrate and lipid metabolism, such a storage in chronic hyperglycaemia seems to be of importance.