Interactions Between Growth Hormone Releasing Hormone, Somatostatin and Galanin in the Control of Growth Hormone Secretion
Growth hormone (GH) is secreted episodically in man and animals (1,2). This rhythmic secretory pattern results from the interactions between two neuropeptides, GH-releasing hormone (GHRH) and somatostatin. Evidence supports the hypothesis that these two hypophysiotrophic factors are themselves released in an episodic manner into the portal circulation, thereby directly influencing the pituitary somatotrophs. Our understanding of the interactions between GHRH and somatostatin at both the hypothalamic and pituitary levels, although extensively investigated, is incomplete.
KeywordsGrowth Hormone Arcuate Nucleus Serum Growth Hormone Anterior Pituitary Cell Growth Hormone Concentration
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