Studies of the physiology and pathophysiology of the pancreatic D cell

The recent discovery by Luft and associates¹ and by Dubois² of somatostatin-containing islet cells, subsequently identified as D cells, ^3-6 has aroused speculation concerning their physiologic and pathophysiologic roles. The ability of somatostatin to inhibit insulin and glucagon secretion has suggested that the function of the D cell may be to restrain the secretory activity of its neighboring cells, perhaps via local or paracrine action. ^7-10 The possibility that pancreatic somatostatin is a hormone secreted into the circulation to act upon remote target tissues has received little attention. The present communication will review ongoing studies in our laboratories that point to an endocrine role for somatostatin in nutrient homeostasis and suggest that D cell function may be abnormal in certain forms of diabetes.