Exocytosis in mammalian cells. VI. Temperature dependence of pancreatic exocrine secretion

Abstract

The effects of temperature on amylase secretion in vitro were measured [in rats] under stimulated and nonstimulated conditions. In the 2 cases a very rapid decrease of secretory rate was observed between 37-25.degree. C (60-70%). The decrease was less pronounced between 25-15.degree. C. Between 15-13.degree. C a drop of secretory activity (10%) was observed under stimulation whereas an increase was measured in absence of stimulus. At lower temperatures the rate of secretion falls again abruptly. The secretory pattern of amylase from pancreas in vitro as a function of temperature is evidently very different under stimulated and nonstimulated conditions. The abrupt change of secretory activity between 15-13.degree. C can apparently correspond to a change of physical state of the membranes involved in the exocytosis process.