Release of Neuropeptides from Magnocellular Neurones: Does Anatomical Compartmentation Have a Functional Significance?
The mammalian magnocellular neurosecretory system which projects to the capillaries of the neural lobe has, for many years, served as a useful and archetypal model in the study of mechanisms of neuropeptide secretion. The magnocellular neurones produce either vasopressin (VP) or oxytocin (OT), and other peptides including dynorphin, from precursors synthesized in the cell bodies and packaged into neurosecretory granules (NSG). Many of the typically varicose axons transport the maturing neurosecretory product in NSG through the median eminence to the neural lobe where it is either stored, released by exocytosis into the systemic circulation, or degraded.
KeywordsTannic Acid Nerve Ending Median Eminence Nephrogenic Diabetes Insipidus Neurosecretory Granule
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