The significance of the Na+/K+ pump for somatostatin release.

The influence of the Na+/K+ pump on somatostatin secretion from the isolated perfused canine pancreas was investigated. The somatostatin secretion was reversibly increased in response to addition of ouabain (10(-5) mol/l) and to omission of extracellular K+, procedures which are known to cause a blockade of the Na+/K+ pump. The stimulatory effect on somatostatin release was abolished during calcium depletion. The results suggest that the operation of the Na+/K+ pump plays an important role for the somatostatin secretion. The action of the Na+/K+ pump on the secretory function of the D-cells is dependent on the presence of extracellular calcium.