THE RELATION OF EXTERNAL PANCREATIC SECRETION TO VARIATIONS IN BLOOD SUGAR

Abstract

All observations were conducted on fasting unanesthetized dogs having Inlow pancreatic fistulas or duodenal cannulas through which the major pancreatic ducts were intubated. Pancreatic secretion was observed in fasting animals lying comfortably on a table. In 5 Inlow fistulas, which secreted large quantities of pancreatic juice, the adm. of insulin (1 unit per kg. subcut.) or glucose (1 g. per kg. intraven.) failed to produce consistent alterations in the vol. and proteolytic activity of pancreatic juice. In contrast 8 dogs. which secreted only small vols. of juice during the fast, showed marked gastric hypermotility and pancreatic augmentation when hypoglycemia (25-40 mg%) appeared. Intraven. insulin, however, initiated a transient inhibition of motility and secretion immediately following the inj. Incomplete vagotomy prevented the hypermotility of insulin hypoglycemia without altering the pancreatic augmentation while complete vagotomy (both vagi cut in the neck) abolished the usual hypoglycemic responses of the stomach and pancreas. Sub-muscular pyloric separation in 3 dogs abolished the pancreatic augmentation previously observed during hypoglycemia. In most of the expts. intraven. glucose inhibited for short periods both gastric motility and pancreatic secretion. Spontaneous alterations in the blood sugar in 7 dogs were unrelated to spontaneous variations in pancreatic secretion and gastric motility.