scholarly journals Frequency-Dependent Regulation of Follicle-Stimulating Hormone β by Pulsatile Gonadotropin-Releasing Hormone Is Mediated by Functional Antagonism of bZIP Transcription Factors

2009 ◽  
Vol 30 (4) ◽  
pp. 1028-1040 ◽  
Author(s):  
Nick A. Ciccone ◽  
Shuyun Xu ◽  
Charlemagne T. Lacza ◽  
Rona S. Carroll ◽  
Ursula B. Kaiser
Keyword(s):  
Molecular Mechanisms ◽  
Follicle Stimulating Hormone ◽  
Critical Role ◽  
Reproductive Function ◽  
Gonadotropin Releasing Hormone ◽  
Stimulatory Action ◽  
Frequency Dependent ◽  
Releasing Hormone ◽  
Pulsatile Gnrh ◽  
Stimulating Hormone

ABSTRACT Oscillatory synthesis and secretion of the gonadotropins, follicle-stimulating hormone (FSH) and luteinizing hormone (LH), under the control of pulsatile hypothalamic gonadotropin-releasing hormone (GnRH), is essential for normal reproductive development and fertility. The molecular mechanisms by which various patterns of pulsatile GnRH regulate gonadotrope responsiveness remain poorly understood. In contrast to the α and LHβ subunit genes, FSHβ subunit transcription is preferentially stimulated at low rather than high frequencies of pulsatile GnRH. In this study, mutation of a cyclic AMP response element (CRE) within the FSHβ promoter resulted in the loss of preferential GnRH stimulation at low pulse frequencies. We hypothesized that high GnRH pulse frequencies might stimulate a transcriptional repressor(s) to attenuate the action of CRE binding protein (CREB) and show that inducible cAMP early repressor (ICER) fulfills such a role. ICER was not detected under basal conditions, but pulsatile GnRH stimulated ICER to a greater extent at high than at low pulse frequencies. ICER binds to the FSHβ CRE site to reduce CREB occupation and abrogates both maximal GnRH stimulation and GnRH pulse frequency-dependent effects on FSHβ transcription. These data suggest that ICER production antagonizes the stimulatory action of CREB to attenuate FSHβ transcription at high GnRH pulse frequencies, thereby playing a critical role in regulating cyclic reproductive function.

scholarly journals Role of Kisspeptin in Puberty in Humans

2020 ◽  
pp. 92-97
Author(s):  
Ravi Kant ◽  
Mahendra Kumar Meena
Keyword(s):  
Reproductive Biology ◽  
Conventional Treatment ◽  
Hypogonadotropic Hypogonadism ◽  
Follicle Stimulating Hormone ◽  
Gonadotropin Releasing Hormone ◽  
Pilot Studies ◽  
Releasing Hormone ◽  
Infertile Couples ◽  
Stimulating Hormone

Kisspeptin or GPR-54 is a product of KISS 1 gene regulating the production of gonadotropin releasing hormone (GnRH), luteinizing (LH) as well follicle stimulating hormone (FSH). Both LH and FSH are important hormones for reproduction in animals as well in humans. The recognition of Kisspeptin has a landmark bearing in reproductive biology. Few recent pilot studies have convincingly proven it to be a promising molecule in treating infertile couples especially those having hypogonadotropic hypogonadism not responding to conventional treatment.

scholarly journals Annual Change of Reproductive Hormones in Female Angora Goats

2017 ◽  
Vol 5 (4) ◽  
pp. 343
Author(s):  
Erkan Pehlivan ◽  
Hüseyin Polat ◽  
Gürsel Dellal
Keyword(s):  
Luteinizing Hormone ◽  
Repeated Measures ◽  
Follicle Stimulating Hormone ◽  
Reproductive Hormones ◽  
Gonadotropin Releasing Hormone ◽  
Blood Samples ◽  
Releasing Hormone ◽  
Angora Goats ◽  
Turkish State ◽  
Stimulating Hormone

In this research, annual changes of melatonin, gonadotropin-releasing hormone, follicle stimulating hormone, luteinizing hormone, estrogen, testosterone and progesterone were studied on 6 heads of 1.5 years old female Angora goat. To determine hormones concentrations, blood samples were taken from jugular vein of each goat in every month for a year. The blood samples were centrifuged at 4000xg for 5 min. and serum was stored at -20°C until analyses time. Hormones analyses in the serum were performed by enzyme immunoassay (EIA) method. Monthly climatic values and photoperiod were obtained from the Turkish State Meteorological Service and temperature-humidity index was calculated with climatic values. In the study, in order to determine any possible differences in the observed hormones concentrations with respect to months, repeated measures ANOVA analysis was performed. As a result of statistical analysis, there were no significant differences among the months for gonadotropin-releasing hormone, follicle stimulating hormone and testosterone concentration, while significant differences were found among the months for melatonin, luteinizing hormone and progesterone, and estrogen concentration in female Angora goats. According the results of this study, could be concluded that the releases of reproductive hormones examined in female Angora goats was seasonally dependent.

Orchidectomy selectively increases follicle-stimulating hormone secretion in gonadotropin-releasing hormone antagonist-treated male rats

1995 ◽  
Vol 132 (3) ◽  
pp. 357-362 ◽  
Author(s):  
M Tena-Sempere ◽  
L Pinilla ◽  
E Aguilar
Keyword(s):  
Gnrh Antagonist ◽  
Follicle Stimulating Hormone ◽  
Hormone Secretion ◽  
Gonadotropin Releasing Hormone ◽  
Male Rats ◽  
Gonadotropin Secretion ◽  
Releasing Hormone ◽  
Treated Male ◽  
Lh Secretion ◽  
Stimulating Hormone

Tena-Sempere M, Pinilla L, Aguilar E. Orchidectomy selectively increases follicle-stimulating hormone secretion in gonadotropin-releasing hormone agonist-treated male rats. Eur J Endocrinol 1995;132: 357–62. ISSN 0804–4643 The pituitary component of the feedback mechanisms exerted by testicular factors on gonadotropin secretion was analyzed in adult male rats treated with a potent gonadotropin-releasing hormone (GnRH) antagonist. In order to discriminate between androgens and testicular peptides, groups of males were orchidectomized (to eliminate androgens and non-androgenic testicular factors) or injected with ethylene dimethane sulfonate (EDS), a selective toxin for Leydig cells (to eliminate selectively androgens) and treated for 15 days with vehicle or the GnRH antagonist Ac-d-pClPhe-d-pClPhe-d-TrpSer-Tyr-d-Arg-Leu-Arg-Pro-d-Ala-NH2CH3COOH (Org.30276, 5 mg/kg/72 hours). Serum concentrations of luteinizing hormone (LH) and follicle-stimulating hormone (FSH) were measured 7 and 14 days after the beginning of treatment. We found that: in males treated with GnRH antagonist, orchidectomy or EDS treatment did not induce any increase in LH secretion; and orchidectomy, but not EDS treatment, increased FSH secretion in GnRH-treated males. The present results show that negative feedback of testicular factors on LH secretion is mediated completely through changes in GnRH actions. In contrast, a part of the inhibitory action of the testis on FSH secretion is exerted directly at the pituitary level. It can be hypothesized that non-Leydig cell testicular factor(s) inputs at different levels of the hypothalamic–pituitary axis in controlling LH and FSH secretion. Manuel Tena-Sempere, Department of Physiology, Faculty of Medicine, University of Córdoba, 14004 Córdoba, Spain

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