CONTEXT: Complex changes in GnRH secretion occur with aging in women, but little is known about the effect of aging on the pituitary per se. OBJECTIVE: The aim of the study was to determine whether pituitary responsiveness to GnRH is attenuated with aging. DESIGN AND SETTING: A GnRH antagonist and graded doses of GnRH were used to isolate pituitary responsiveness in Clinical Research Center studies at an academic medical center. SUBJECTS: Subjects were healthy postmenopausal women (PMW) aged 48-57 yr (n = 10) or 70-77 yr (n= 9). INTERVENTIONS: A suppressive dose of the NAL-GLU GnRH antagonist (150 microg/kg sc) was administered and was followed by GnRH doses of 25, 75, 250, or 750 ng/kg iv every 4 h. RESULTS: The LH response to GnRH was attenuated with aging (P = 0.05) with an interaction between age and dose (P = 0.01) such that the LH amplitude was less in older PMW at the higher doses (250 ng/kg, 50 +/- 9 vs. 29 +/- 4.9 IU/liter, for young and old PMW, respectively, P = 0.02; and 750 ng/kg, 97.7 +/- 11 vs. 70.2 +/- 9.3 IU/liter, P = 0.002), but not the lower doses of GnRH. The FSH response to GnRH was also attenuated with aging in PMW (P = 0.005). CONCLUSIONS: In studies that isolated the pituitary from endogenous GnRH stimulation, aging attenuated the LH and FSH responses to exogenous GnRH in PMW. These studies indicate that the pituitary plays a role in the decline in gonadotropin levels with aging, further supporting the potential contribution of age-associated changes in both hypothalamic and pituitary function to reproductive senescence.
CONTEXT: Complex changes in GnRH secretion occur with aging in women, but little is known about the effect of aging on the pituitary per se. OBJECTIVE: The aim of the study was to determine whether pituitary responsiveness to GnRH is attenuated with aging. DESIGN AND SETTING: A GnRH antagonist and graded doses of GnRH were used to isolate pituitary responsiveness in Clinical Research Center studies at an academic medical center. SUBJECTS: Subjects were healthy postmenopausal women (PMW) aged 48-57 yr (n = 10) or 70-77 yr (n= 9). INTERVENTIONS: A suppressive dose of the NAL-GLU GnRH antagonist (150 microg/kg sc) was administered and was followed by GnRH doses of 25, 75, 250, or 750 ng/kg iv every 4 h. RESULTS: The LH response to GnRH was attenuated with aging (P = 0.05) with an interaction between age and dose (P = 0.01) such that the LH amplitude was less in older PMW at the higher doses (250 ng/kg, 50 +/- 9 vs. 29 +/- 4.9 IU/liter, for young and old PMW, respectively, P = 0.02; and 750 ng/kg, 97.7 +/- 11 vs. 70.2 +/- 9.3 IU/liter, P = 0.002), but not the lower doses of GnRH. The FSH response to GnRH was also attenuated with aging in PMW (P = 0.005). CONCLUSIONS: In studies that isolated the pituitary from endogenous GnRH stimulation, aging attenuated the LH and FSH responses to exogenous GnRH in PMW. These studies indicate that the pituitary plays a role in the decline in gonadotropin levels with aging, further supporting the potential contribution of age-associated changes in both hypothalamic and pituitary function to reproductive senescence.
Authors: J E Hall; T D Brodie; T M Badger; J Rivier; W Vale; P M Conn; D Schoenfeld; W F Crowley Journal: J Clin Endocrinol Metab Date: 1988-09 Impact factor: 5.958
Authors: Mark Jentoft; Bernd W Scheithauer; Olga Moshkin; Eva Horvath; Phillip C Collins; Luis V Syro; Kalman Kovacs Journal: Endocr Pathol Date: 2012-06 Impact factor: 3.943
Authors: Pulak R Manna; Cloyce L Stetson; Carol Daugherty; Ikue Shimizu; Peter J Syapin; Ghislaine Garrel; Joelle Cohen-Tannoudji; Ilpo Huhtaniemi; Andrzej T Slominski; Kevin Pruitt; Douglas M Stocco Journal: Mech Ageing Dev Date: 2015-08-21 Impact factor: 5.432