Why oxytocin and vasopressin called as 'neuro hormone'?

Why Oxytocin and Vasopressin called as 'neuro hormone'?

-souti das

The posterior pitutary secretes two hormone oxytocin and vasopressin(ADH).The hormones are synthesized within the cell bodies of large magnocellular neurons lying in the supraoptic and paraventricular nuclei (PVN) of the hypothalamus.

The posterior pituitary hormones are transported in association with specific proteins, called neurophysins , along the axons of the neurons to end in those nerve terminals which lie within the posterior lobe. Prior to secretion, these hormones are stored in secretory granules either in the nerve terminals or in the varicosites called herring bodies . The hormones are secreted in response to nerve impulses originating in the supraoptic and PVN and enter the capillary blood that perfuse the neural lobe. Both oxytocin and vasopressin are secreted in ca2+dependent exocytosis manner similar to the secretion of neurotransmitters at other nerve terminals.

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