Growth hormone-releasing hormone: Not only a neurohormone

Department of Biochemistry, University of Athens Medical School, Mikras Asias 75, 11527 Athens, Greece.
Trends in Endocrinology and Metabolism (Impact Factor: 9.39). 04/2011; 22(8):311-7. DOI: 10.1016/j.tem.2011.03.006
Source: PubMed


Growth hormone-releasing hormone (GHRH) is mostly thought to act by stimulating the production and release of growth hormone from the pituitary. However, this neuropeptide emerges as a rather pleiotropic hormone in view of the identification of various extrapituitary sources for GHRH production, as well as the demonstration of a direct action of GHRH on several tissues other than the pituitary. Non-pituitary GHRH has a wide spectrum of activity, exemplified by its ability to modulate cell proliferation, especially in malignant tissues, to regulate differentiation of some cell types, and to promote healing of skin wounds. These findings extend the role of GHRH and its analogs beyond its accepted regulation of somatotropic activity and indicate new possibilities for therapeutic intervention.

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    • "Both the GHRH-R and the bioactive SV1 receptor, the latter of which is expressed in HL-MVEC, are coupled to heterotrimeric G proteins (Mayo et al., 1995; Sherwood et al., 2000; Kiaris et al., 2011). The latter consist of α, β, and γ subunits and function as transducers of signals from G-protein coupled receptors (GPCRs). "
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