TY - JOUR
T1 - Human GH pulsatility
T2 - An ensemble property regulated by age and gender
AU - Veldhuis, Johannes D.
AU - Bowers, C. Y.
N1 - Funding Information:
The Authors thank Jean Plote for excellent editorial support. This work was supported in part by the National Center for Research Resources via General Clinical Research Center grant RR00585 to the Mayo Clinic and Foundation and NIH ROI AG 14799-05 and AG 19695-02.
PY - 2003/9
Y1 - 2003/9
N2 - Age and gender impact the full repertoire of neurohormone systems, including most prominently the somatotropic, gonadotropic and lactotropic axes. For example, daily GH production is approximately 2-fold higher in young women than men and varies by 20-fold by sexual developmental status and age. Deconvolution estimates of 24-h GH secretion rates exceed 1200 μg/m2 in adolescents and fall below 60 μg/m2 in aged individuals. The present overview highlights plausible factors driving such lifetime variations in GH availability, i.e., estrogen, aromatizable androgen, hypothalamic peptides and negative feedback by GH and IGF-I. In view of the daunting complexity of potential neuromodulatory signals, we underline the utility of conceptualizing a simplified three-peptide regulatory ensemble of GHRH, GHRP (ghrelin) and somatostatin. The foregoing signals act as individual and conjoint mediators of adaptive GH control. Regulation is enforced at 3-fold complementary time scales, which embrace pulsatile (burst-like), entropic (orderly) and 24-h rhythmic (nycthemeral) modes of GH release. This unifying platform offers a convergent perspective of multivalent control of GH outflow.
AB - Age and gender impact the full repertoire of neurohormone systems, including most prominently the somatotropic, gonadotropic and lactotropic axes. For example, daily GH production is approximately 2-fold higher in young women than men and varies by 20-fold by sexual developmental status and age. Deconvolution estimates of 24-h GH secretion rates exceed 1200 μg/m2 in adolescents and fall below 60 μg/m2 in aged individuals. The present overview highlights plausible factors driving such lifetime variations in GH availability, i.e., estrogen, aromatizable androgen, hypothalamic peptides and negative feedback by GH and IGF-I. In view of the daunting complexity of potential neuromodulatory signals, we underline the utility of conceptualizing a simplified three-peptide regulatory ensemble of GHRH, GHRP (ghrelin) and somatostatin. The foregoing signals act as individual and conjoint mediators of adaptive GH control. Regulation is enforced at 3-fold complementary time scales, which embrace pulsatile (burst-like), entropic (orderly) and 24-h rhythmic (nycthemeral) modes of GH release. This unifying platform offers a convergent perspective of multivalent control of GH outflow.
KW - Aging
KW - Sex steroid
KW - Somatotropin
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U2 - 10.1007/BF03345229
DO - 10.1007/BF03345229
M3 - Review article
C2 - 14964431
AN - SCOPUS:0345737276
SN - 0391-4097
VL - 26
SP - 799
EP - 813
JO - Journal of endocrinological investigation
JF - Journal of endocrinological investigation
IS - 9
ER -