TY - JOUR
T1 - Females secrete growth hormone with more process irregularity than males in both humans and rats
AU - Pincus, Steven M.
AU - Gevers, Evelien F.
AU - Robinson, Iain C.A.F.
AU - Van Den Berg, Gerrit
AU - Roelfsema, Ferdinand
AU - Hartman, Mark L.
AU - Veldhuis, Johannes D.
PY - 1996
Y1 - 1996
N2 - In humans, serum growth hormone (GH) concentrations are significantly higher in women than in men, but the neuroendocrine mechanisms that underlie such gender differences are not known. We compared normal episodic GH secretion in males and females in three distinct settings: two human studies employing quite different assay techniques (immunoradiometric assay and a high-sensitivity immunofluorimetric method) and a rat study. To quantify the amount of regularity in data, we utilized approximate entropy (ApEn), a scale- and model-independent statistic. In each study, females exhibited significantly greater statistical irregularity in GH concentration series than their male counterparts (P < 10-3 for each human study, P < 10-6 for the rat study), implying that mass and mode of GH secretion are regulated differently in males and females. The regularity comparisons indicated complete gender separation (100% specificity and sensitivity) for the rat study and nearly complete separation for the immunofluorimetric assay study. The consistency and statistical significance of these findings suggest that this gender difference may be broadly based within higher animals and that this may he readily evaluated objectively by analysis of ApEn.
AB - In humans, serum growth hormone (GH) concentrations are significantly higher in women than in men, but the neuroendocrine mechanisms that underlie such gender differences are not known. We compared normal episodic GH secretion in males and females in three distinct settings: two human studies employing quite different assay techniques (immunoradiometric assay and a high-sensitivity immunofluorimetric method) and a rat study. To quantify the amount of regularity in data, we utilized approximate entropy (ApEn), a scale- and model-independent statistic. In each study, females exhibited significantly greater statistical irregularity in GH concentration series than their male counterparts (P < 10-3 for each human study, P < 10-6 for the rat study), implying that mass and mode of GH secretion are regulated differently in males and females. The regularity comparisons indicated complete gender separation (100% specificity and sensitivity) for the rat study and nearly complete separation for the immunofluorimetric assay study. The consistency and statistical significance of these findings suggest that this gender difference may be broadly based within higher animals and that this may he readily evaluated objectively by analysis of ApEn.
KW - approximate entropy
KW - gender differences
KW - neuroendocrine mechanisms
KW - pulsatility
KW - somatostatin
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U2 - 10.1152/ajpendo.1996.270.1.e107
DO - 10.1152/ajpendo.1996.270.1.e107
M3 - Article
C2 - 8772482
AN - SCOPUS:0030041976
SN - 0193-1849
VL - 270
SP - E107-E115
JO - American Journal of Physiology - Endocrinology and Metabolism
JF - American Journal of Physiology - Endocrinology and Metabolism
IS - 1 33-1
ER -