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Janet E Hall

Publications and source records attributed to Janet E Hall.

23 records · Page 2Linked to original sources
PubMed2002

Evidence that GnRH decreases with gonadal steroid feedback but increases with age in postmenopausal women.

UNLABELLED: Studies of the effects of gonadal steroid negative feedback and age on the hypothalamic-pituitary axis in postmenopausal women (PMW) have identified significant but inconsistent changes in gonadotropin dynamics. In the current study, we investigated the effect of gonadal steroid replacement and age on overall GnRH secretion estimated by using submaximal GnRH receptor blockade. Twenty-four healthy PMW, 45-55 yr (n = 13) and 70-80 yr (n = 11), were studied. Subjects were studied at baseline (BL) on no hormone replacement therapy, after 1 month of transdermal estrogen (50 microg/d; E) and again after a further month of E and 7 d of transvaginal progesterone (100 mg bid; E + P). At each admission, blood was sampled every 30 min for 4 (BL and E) or 8 h (E + P) before and 10 h after sc administration of a submaximal dose (5 microg/kg) of the NAL-GLU GnRH antagonist ([Ac-D2Nal(1), D4ClPhe(2), DPal(3), Arg(5), DGlu(AA)(6), DAla(10)] GnRH). Percent inhibition of LH was calculated by expressing the difference between the nadir following GnRH antagonist administration and the preantagonist baseline as a percent of the baseline. Physiologic E and P levels were achieved with the appropriate hormone replacement regimens. Mean LH levels decreased from baseline with E alone and decreased further with E + P (81.4 +/- 6.6, 68.2 +/- 8.1 and 48.0 +/- 4.3 IU/liter, respectively; P < 0.005). Percent inhibition of LH following submaximal GnRH receptor blockade decreased with age (57.6 +/- 1.8% in young PMW vs. 51.4 +/-2.2% in old PMW; P < 0.05) implying an increase in GnRH secretion with age. There was an increase in percent inhibition of LH in response to submaximal GnRH receptor blockade with E and a further increase with E + P (54.8 +/-1.5%, 58.8 +/- 1.9% and 69.9 +/- 2.8%, respectively; P < 0.05), indicating a progressive decrease in endogenous GnRH secretion with gonadal steroid feedback. Mean LH and FSH levels were lower at baseline in old compared with young PMW. However, the effect of gonadal steroid feedback on endogenous GnRH secretion was similar in young and old PMW. IN CONCLUSION: 1) The overall quantity of GnRH secretion increases with age as demonstrated by the progressive decrease in LH inhibition following submaximal GnRH antagonist administration with increasing age; 2) E negative feedback is associated with a decrease in GnRH secretion (as indicated by an increased percent inhibition of LH following submaximal GnRH receptor blockade); 3) E2 and P are associated with a further decease in overall amount of GnRH secreted; and 4) Age does not dampen the inhibition of hypothalamic GnRH secretion by E and P in PMW.

Aged↗
PubMed2002

Negative feedback effects of gonadal steroids are preserved with aging in postmenopausal women.

There is now evidence for alterations in the neuroendocrine control of the reproductive axis with aging, but its sensitivity to gonadal steroid negative feedback remains controversial. To examine the independent effect of age and gonadal steroid negative feedback, younger (45-55 yr; n = 7) and older (70-80 yr; n = 6) postmenopausal women (PMW) were studied at baseline on no HRT, after 1 month of transdermal estrogen (50 microg/d; E) and again after a further month of E and 7 d of transvaginal progesterone (P) (100 mg bid; E + P). At each admission, blood was sampled every 5 min for 8 h for measurement of gonadotropin free alpha-subunit (FAS), which was used as a marker of GnRH pulse frequency. LH and FSH were measured in pooled samples. Midfollicular and midluteal phase levels of E2 and P were achieved during the E and E + P treatments and were not different between younger and older PMW. There was a negative feedback effect of E and E + P on mean LH (P < 0.0001) and an additional effect of age (P < 0.003), with older women having lower values throughout. Mean FSH was also decreased with E and E + P (P < 0.0001) and was consistently lower in the older women (P < 0.05). Mean FAS levels decreased with hormonal treatment (P < 0.0001) and age (P < 0.001), but the effect of hormonal treatment was attenuated in the older group (P < 0.005). FAS pulse frequency was unchanged with addition of E, but dramatically decreased with E + P (P < 0.002). Both hormonal replacement (P < 0.05) and age (P < 0.005) decreased FAS pulse amplitude, an effect that was attributable entirely to E as there was no additional change with E + P. These studies indicate that: 1) both age and gonadal steroids independently decrease mean LH, FSH, and FAS in PMW; 2) responsiveness to steroid negative feedback on FAS is attenuated with aging in absolute but not relative terms, whereas the effect on mean levels of LH and FSH is clearly preserved; and 3) FAS pulse frequency is unchanged with E2 administration but decreases dramatically with addition of P in both old and young PMW.

Aged↗
PubMedDate not supplied

Vasomotor symptoms are associated with depression in perimenopausal women seeking primary care.

OBJECTIVE: To compare the relationship between vasomotor symptoms (hot flushes and night sweats) and depression in perimenopausal women with that in postmenopausal and older premenopausal women. DESIGN: Questionnaire data assessing current depressive symptoms (Center for Epidemiologic Studies Depression Scale), hot flushes, night sweats, menopausal status, depression history, hormonal therapy use, and demographic characteristics were collected from women aged 40 to 60 years seeking primary care. Multivariable logistic regression models were used to examine the relationship between vasomotor symptoms and depression. RESULTS: Depression (defined by a Center for Epidemiologic Studies Depression Scale score >/= 25) was observed in 14.9% of 141 perimenopausal women, 13.9% of 151 postmenopausal women, and 7.6% of 184 older premenopausal women. Recent vasomotor symptoms were reported by 53.9% of perimenopausal women, 43.7% of postmenopausal women, and 20.7% of older premenopausal women. Perimenopausal women with vasomotor symptoms were 4.39 times more likely to be depressed than those without vasomotor symptoms (95% CI, 1.40-13.83), an association that did not change after controlling for depression history. In contrast with perimenopausal women, postmenopausal and older premenopausal women with vasomotor symptoms did not have a significantly greater risk for depression than women of the same menopausal status without vasomotor symptoms (adjusted odds ratios, 1.28 and 1.77; 95% CI, 0.47-3.46 and 0.53-5.89, respectively). CONCLUSIONS: Hot flushes and night sweats are associated with depression in perimenopausal women. Further investigation is warranted to elucidate the mechanism by which hot flushes may be associated with depression in perimenopausal women and not in postmenopausal or older premenopausal women.

Adult↗
PubMedDate not supplied

Estrogen therapy selectively enhances prefrontal cognitive processes: a randomized, double-blind, placebo-controlled study with functional magnetic resonance imaging in perimenopausal and recently postmenopausal women.

OBJECTIVE: Estrogen therapy (ET) seems to differentially effect cognitive processes in younger versus older postmenopausal women, suggesting a window of opportunity when ET is most beneficial. Cognitive improvement in younger postmenopausal women has been attributed to ET's influence on hot flushes and sleep, but empiric examination of the mediating role of menopause symptoms versus direct effects of ET on the brain is limited. DESIGN: In a double-blind trial, 52 women were randomly assigned to estradiol 0.05 mg/day (n = 26) or placebo transdermal patches (n = 26) for 12 weeks. Women completed tests of memory, learning, and executive functioning, and hot flush and sleep assessments at baseline and study end. A subset of women (five ET treated, six placebo treated) also underwent blood oxygenation level-dependent (BOLD) functional magnetic resonance imaging (fMRI) studies. RESULTS: Nondepressed perimenopausal and postmenopausal women were studied. The majority had hot flushes and sleep impairment. Compared with placebo, ET selectively reduced errors of perseveration during verbal recall (P = 0.03), a frontal system-mediated function, but did not influence other cognitive processes. Women with baseline hot flushes had greater cognitive benefit with ET (P < 0.05). Cognitive benefit was not associated with sleep problems or its improvement. Measures of fMRI BOLD activation during tests of verbal and spatial working memory showed significant increases in frontal system activity with ET (P < 0.001). CONCLUSIONS: Estrogen therapy selectively improves executive functioning as demonstrated by reduced perseverative errors and prefrontal cortex activation during verbal recall tasks. Cognitive improvement with ET is associated with hot flushes, but not with sleep, suggesting that ET has a direct central nervous system effect, rather than an indirect effect mediated through improvement of sleep.

Administration, Cutaneous↗