CERTAIN QUANTITATIVE ASPECTS OF THE PANCREATIC RESPONSE TO SECRETIN

Abstract

A secretin concentrate was injected intraven. in 25 anesthetized dogs in graded doses ranging from minimal to maximal. In over half the animals a pancreatic response was obtained with 0.25 mg. of material. Increasing the secretin dosage stimulated an increase in pancreatic secretion which was at first rapid, then more gradual, and finally a dosage was attained which caused the pancreas to secrete at its maximum capacity, and beyond which no greater response resulted. The conc.-action curve obtained from this data assumed an S-shape and the curves were similar for the response during the first 10 mins. following inj. and for the response for the total duration of action of secretin; in the former case the secretory values were on a lower level. Secretin was also injected continuously in increasing amts. with analogous results; these expts. showed that the minimal effective amt. of pure secretin base necessary to stimulate the pancreas of the anesthetized dog to secrete is 0.0007 mg., and the amt. required to stimulate the gland maximally is 0.014 mg.