Mechanisms of storage and exocytosis in neuroendocrine tumors.

Excitatory and inhibitory neurotransmitters and biogenic amines are important signaling molecules stored by and released from endocrine cells. They are either synthesized or taken up by endocrine cells and subsequently stored in secretory vesicles. Analysis of these storage mechanisms and of the receptors of these paracrine signaling molecules revealed important cross-talk within endocrine glands which add to storage and release of peptide hormones.