Release of dopamine beta-hydroxylase and chromogranin A upon stimulation of the splenic nerve.

Two proteins present in noradrenergic vesicles of the splenic nerve (dopamine beta-hydroxylase and chromogranin A) are released into the perfusate from the spleen when the splenic nerve is stimulated. Experiments in which drugs were added to the perfusion fluid showed that the proteins were released from terminals of the splenic nerve. There was a correlation between the amounts of the proteins released and the quantity of noradrenaline released; and the release process was dependent upon calcium. It is suggested that the proteins are released from the large dense-cored vesicles present in the terminals of the splenic nerve, and that secretion from these vesicles occurs by exocytosis.