SOMATOTROPIC AXIS AND BODY-WEIGHT IN PREMENOPAUSAL AND POSTMENOPAUSALWOMEN - EVIDENCE FOR A NEUROENDOCRINE DERANGEMENT, IN ABSENCE OF CHANGES OF INSULIN-LIKE-GROWTH-FACTOR BINDING-PROTEIN CONCENTRATIONS
F. Bernardi et al., SOMATOTROPIC AXIS AND BODY-WEIGHT IN PREMENOPAUSAL AND POSTMENOPAUSALWOMEN - EVIDENCE FOR A NEUROENDOCRINE DERANGEMENT, IN ABSENCE OF CHANGES OF INSULIN-LIKE-GROWTH-FACTOR BINDING-PROTEIN CONCENTRATIONS, Human reproduction, 13(2), 1998, pp. 279-284
The altered function of the somatotropic axis observed in perimenopaus
e may underlie the changes in body weight and fat distribution, The ai
m of the present study was to evaluate, in pre-menopausal and post-men
opausal women with body mass index (BMI) greater than or equal to or <
25, the basal plasma levels of growth hormone (GH), insulin-like growt
h factor (IGF)-I and -II, IGF binding protein (IGFBP)-1 and -3, and th
e response of GH and IGFBP-1 and -3 to GH releasing hormone (GHRH) and
GHRH plus arginine tests, GH and IGF-I basal concentrations were sign
ificantly higher in pre-menopausal than in post-menopausal women, whil
e IGF-II, IGFBP-1 and IGFBP-3 concentrations did not vary significantl
y, IGFBP-1, but not IGFBP-3, concentrations were higher in lean than i
n obese patients, Insulin concentrations were significantly higher in
obese patients, while no differences were observed between pre-menepau
sal and post-menopausal women, In all subjects, GH concentrations incr
eased significantly during GHRH test; pre-menopausal and lean women sh
owed a higher response compared to post-menopausal and obese women, Th
e GHRH plus arginine test stimulated GH response in all women, irrespe
ctive of age and BMI, IGFBP-1 and -3 concentrations did not vary in re
sponse to GHRH or GHRH plus arginine tests, The somatotropic axis unde
rgoes modifications in post-menopausal women, apparently not involving
IGFBP-1 and -3, Arginine infusion restores the response of GH to GHRH
, in both post-menopausal and obese subjects, A somatostatinergic hype
ractivity at the climateric period may underlie the changes both in bo
dy weight and somatotropic axis.