Pulsatile pattern of LH secretion in relation to the sex steroid milieu

Author(s):  
J. Schoemaker ◽  
D. Hemrika
Keyword(s):  
2013 ◽  
Vol 304 (9) ◽  
pp. E934-E943 ◽  
Author(s):  
Julia Johansson ◽  
Leanne Redman ◽  
Paula P. Veldhuis ◽  
Antonina Sazonova ◽  
Fernand Labrie ◽  
...  

Acupuncture has been demonstrated to improve menstrual frequency and to decrease circulating testosterone in women with polycystic ovary syndrome (PCOS). Our aim was to investigate whether acupuncture affects ovulation frequency and to understand the underlying mechanisms of any such effect by analyzing LH and sex steroid secretion in women with PCOS. This prospective, randomized, controlled clinical trial was conducted between June 2009 and September 2010. Thirty-two women with PCOS were randomized to receive either acupuncture with manual and low-frequency electrical stimulation or to meetings with a physical therapist twice a week for 10–13 wk. Main outcome measures were changes in LH secretion patterns from baseline to after 10–13 wk of treatment and ovulation frequency during the treatment period. Secondary outcomes were changes in the secretion of sex steroids, anti-Müllerian hormone, inhibin B, and serum cortisol. Ovulation frequency during treatment was higher in the acupuncture group than in the control group. After 10–13 wk of intervention, circulating levels of estrone, estrone sulfate, estradiol, dehydroepiandrosterone, dehydroepiandrosterone sulfate, androstenedione, testosterone, free testosterone, dihydrotestosterone, androsterone glucuronide, androstane-3α,17β-diol-3-glucuronide, and androstane-3α,17β-diol-17-glucuronide decreased within the acupuncture group and were significantly lower than in the control group for all of these except androstenedione. We conclude that repeated acupuncture treatments resulted in higher ovulation frequency in lean/overweight women with PCOS and were more effective than just meeting with the therapist. Ovarian and adrenal sex steroid serum levels were reduced with no effect on LH secretion.


Author(s):  
S. Karkare ◽  
J. Gilloteaux ◽  
T. R. Kelly

Approximately 1 million people in the United States alone develop gallstones each year. The incidence is higher in women than in men and the ratio being 4 ≥ 1. A correlation has also been suggested between oral contraceptives and cholelithiasis. In addition, postmenopausal or cancer estrogen therapy has been reported to be a factor responsible for gallstone formation. Female sex hormone receptors have been detected not only in the gallbladder musculature, but also in its epithelium. As a follow up to experiments effectuated in the male and the ovariectomized Syrian hamster, this report shows that, a combination of a low cholesterol diet with female sex steroid treatment contributes to the formation of gallstone-like deposits, while modifying the surface epithelium morphology. Syrian hamsters (F1B strain, BioBreeders, Watertown MA) were housed under 12h light: 12 h dark cycle, at 20 °C, fed Purina chow and water ad libitum. Several duration/treatment groups were studied, but this report will focus on data obtained with the group injected weekly with estradiol valerate (E weekly, s.c. 8-10 μg/100 g.b.w., in corn oil) and with i.m. medroxyprogesterone acetate (DepoProvera Upjohn Co., Kalamazoo, MI; 8-10 mg/100 g.b.w.) for a 3-month period. Other parameters (blood and bile) were also studied but not reported here.


1983 ◽  
Vol 102 (4) ◽  
pp. 499-504 ◽  
Author(s):  
M. J. D'Occhio ◽  
B. D. Schanbacher ◽  
J. E. Kinder

Abstract. The acute castrate ram (wether) was used as an experimental model to investigate the site(s) of feedback on luteinizing hormone (LH) by testosterone, dihydrotestosterone and oestradiol. At the time of castration, wethers were implanted subdermally with Silastic capsules containing either crystalline testosterone (three 30 cm capsules), dihydrotestosterone (five 30 cm capsules) or oestradiol (one 6.5 cm capsule). Blood samples were taken at 10 min intervals for 6 h 2 weeks after implantation to determine serum steroid concentrations and to characterize the patterns of LH secretion. Pituitary LH response to exogenous LRH (5 ng/kg body weight) were also determined at the same time. The steroid implants produced serum concentrations of the respective hormones which were either one-third (testosterone) or two-to-four times (dihydrotestosterone, oestradiol) the levels measured in rams at the time of castration. Non-implanted wethers showed rhythmic pulses of LH (pulse interval 40–60 min) and had elevated LH levels (16.1 ± 1.6 ng/ml; mean ± se) 2 weeks after castration. All three steroids suppressed pulsatile LH release and reduced mean LH levels (to below 3 ng/ml) and pituitary LH responses to LRH. Inhibition of pulsatile LH secretion by all three steroids indicated that testosterone as well as its androgenic and oestrogenic metabolites can inhibit the LRH pulse generator in the hypothalamus. Additional feedback on the pituitary was indicated by the dampened LH responses to exogenous LRH.


1975 ◽  
Vol 80 (1_Suppla) ◽  
pp. S76
Author(s):  
N. Parvizi ◽  
F. Elsaesser ◽  
D. Smidt ◽  
F. Ellendorff

2013 ◽  
Author(s):  
Raffaella Radin ◽  
Mirella Moro ◽  
Massimo Scacchi ◽  
Francesco Cavagnini ◽  
Leila Danesi ◽  
...  

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