A neurohormone is any hormone produced and released by neuroendocrine cells into the blood.



They are secreted into the circulation for systemic effect, but they can also have a role of neurotransmitter or other roles such as autocrine or paracrine messenger.



The hypothalamus releasing hormones are neurohypophysial hormones.



These neurons from the hypothalamus extend to the median eminence and posterior pituitary. 



The adrenal medulla produces adrenomedullary hormones in chromaffin cells.



Enterochromaffin cells are  considered neuroendocrine cells due to their structural and functional similarity to chromaffin cells.



Releasing hormones also known as hypothalamic hormones are synthesized by specialized neurons in the hypothalamus. 



Hypothalamic hormones are subsequently transported along neuronal axons to their axon terminals to form the median eminence, where they are stored and released into the hypophyseal portal system. 



After release from the hypophyseal portal system theyrapidly reach the anterior pituitary where they exert their hormonal action. 



Some residual hormones pass into the systemic circulation where they are diluted, degraded and have little effect.



Neurohormone synthesis, and release of those hormones is regulated by hormonal, local and synaptic signals by neurotransmitters.



The neurons secreting their various  neurohormones discharge them as impulses in bursts, causing a pulsatile release which is more efficient than a continuous release.



Hypophysiotropic hormones include:



Thyrotropin-releasing hormone



Corticotropin-releasing hormone



Growth hormone-releasing hormone






Gonadotropin-releasing hormone









Neurohypophysial hormones are synthesized in the magnocellular secretory neurons of the hypothalamus. 



Neurohypophysial hormones


are then transported along neuronal axons within the infundibular stalk to their axon terminals forming the pars nervosa of the posterior pituitary, where they are stored and released into the systemic circulation. 



Neurohormones are synthesized controlled and released by hormonal, local and synaptic signals.



The Neurohypophysial hormones include:









Adrenal medullary hormones are catecholamines secreted from the adrenal medulla by chromaffin cells, neurosecretory cells connected to the central nervous system.



Catecholamines are stored in chromaffin cells, and their synthesis and release are 


co-regulated by synaptic input from their respective pre-synaptic sympathetic neurons, as well as hormonal and local inputs.



The adrenomedullary hormones are:












Enterochromaffin cells in the epithelia lining the lumen of the gastrointestinal  tract secrete serotonin, while enterochromaffin-like cells at the stomach glands secrete histamine. 



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