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

The effects of temperature on amylase secretion in vitro have been measured under stimulated and nonstimulated conditions. In both cases a very rapid decrease of secretory rate was observed between 37 and 25 degrees C (60-70%). The decrease is less pronounced between 25 an 15 degrees C. Between 15 and 13 degrees 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. These results show that the secretory pattern of amylase from pancreas in vitro as a function of temperature is very different under stimulated and nonstimulated conditions. We suggest that the abrupt change of secretory activity between 15 and 13 degrees C could correspond to a change of physical state of the membranes involved in the exocytosis process.