In gonadotropins

Legan SJ, Tsai HW (2003) Oestrogen receptor-alpha and beta immunoreactivity in gonadotropin-releasing hormone neurons after ovariectomy and chronic exposure to oestradiol. J Neuroendocrinol 15 1164-1170... 

There are a variety of constitutively active mutations in the gene encoding the LH receptor. These variants result in gonadotropin-independent disorders such as testotoxicosis and familial male precocious puberty (FMPP) (91). These disorders are inherited in an autosomal dominant, male-limited pattern (92,93). 

Habiby, R. L., Boepple, P., NachtigaU, L., Sluss, P. M., Crowley, W. F., and Jameson, J. L. (1996) Adrenal hypoplasia congenita with hypogonadotropic hypogonadism—evidence that DAX-1 mutations lead to combined hypothalamic and pituitary defects in gonadotropin production. J. Clin. Invest. 98, 1055-1062. 

Layman, L. C., Cohen, D. P., Jin, M., et al. (1998) Mutations in gonadotropin-releasing hormone receptor gene cause hypogonadotropic hypogonadism. Nat. Genet. 18, 14-15. 

Stimulation of spermatogenesis in gonadotropin (FSH, LH) deficiency can be achieved by injection of HMG and HCG. HMG or human menopausal gonadotropin is obtained from the urine of postmenopausal women and is rich in FSH activity. HCG, human chorionic gonadotropin, from the urine of pregnant women, acts like LH. 

Altered skin pigmentation has been previously reported in pregnancy and after sex hormone administration, so the initial surge in gonadotropins after gonadorelin treatment was a probable cause for the first patient s presentation. 

Christian CA, Mobley JL, Moenter SM. Diurnal and estradiol-dependent changes in gonadotropin-releasing hormone neuron firing activity. Proc Natl Acad Sci USA. 2005 102 15682-15687. 

The ovarian cycle is closely tied to circadian rhythms. Elegant studies in rodents have demonstrated that the gonadotropin surge is under 24-h photoperiodic control and that inducing sleep by administration of an anesthetic (e.g., pentobarbital) on the afternoon preceding ovulation causes a delay in gonadotropin surge and ovula-... 

F10. Forman, R. G., Robinson, J., Egan, D., Ross, C., Gosden, B., and Barlow, D. H., Follicular monitoring and outcome of in vitro fertilization in gonadotropin-releasing hormone-agonist-treated cycles. Fertil. Steril. 55, 567-573 (1991). 

Tumor flare occurs in up to 30% of treated patients after the first 4-7 days of gonadorelin therapy, due to an initial surge in gonadotropin concentrations (65). For this reason... 

Jeffcoate S. What are we measuring in gonadotropin assays Acta Endocrinol (Copenh) 1988 288 28-30. 

A5. Albert, A., Use of standards in gonadotropin assays. In Gonadotropins, Proc. Workshop Conf. (E. Rosemberg, ed.), pp. 419-421. Geron-X, Los Altos, California, 1968. 

B14. Butt, W. R., Crooke, A. C., and Wolf, A., Some problems related to the investiga tion of the immunological properties of human pituitary follicle-stimulating hormone. In Gonadotropins Physicochemical and Immunological Properties (G. E, W. Wolstenholme and J. Knight, eds.), CzT)o Found. Study Group (Pap.) 22, 85-106 (1965). 

Prevot V, Croix D, Bouret S, Dutoit S, Tramu G, et al. 1999. Definitive evidence for the existence of morphological plasticity in the external zone of the median eminence during the rat estrous cycle Implication of neuro-glio-endothelial interactions in gonadotropin-releasing hormone release. Neuroscience 94 809-819. 

Eyigor O, Jennes L (1997) Expression of glutamate receptor subunit mRNAs in gonadotropin-releasing hormone neurons during the sexual maturation of the female rat. Neuroendocrinology 66 122-129. 

Pure GnRH antagonists also have been developed these do not cause the initial increase in gonadotropin secretion seen when long-acting GnRH agonists are used. 

Braun, T., Schofield, P.R. and Sprengel, R. (1991) Amino-terminal leucine-rich repeats in gonadotropin receptors determine hormone selectivity. EMBO J. 10 1885-1890. 

Clomiphene Clomiphene is used to induce ovulation in anovulatory women who wish to become pregnant. It is a nonsteroidal compound with tissue-selective actions. By selectively blocking estrogen receptors in the pituitary, clomiphene reduces negative feedback and increases FSH and LH output. The increase in gonadotropins stimulates ovulation. 

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