Gonadotropin-II

At the time of ovulation - which is about 12 hours after onset of the gonadotropin II surge in the female - females release less pheromonal steroids than before. They now become sexually active, receptive, and attractive to males. 

Female rainbow trout, Oncorhynchusmykiss, also release in their urine 17,20jSP. As in goldfish, this pheromone increases the plasma levels of gonadotropin II and testosterone in spermiating males Scott etal, 1994). Levels of 17,20jSP rises within 1 hour of exposure and peak at 3-4 hours. Milt production also increases (Vermeirssenetfl /., 1997). 

Rainbow trout Oncorhynchtis mykiss F M Urinary pheromone ll gonadotropin II tr 17,20/SP ll Testosterone ll Milt production Vermeirssen etal., 1997... 

Scott, A. P., Liley, N. R., and Vermeirssen, E. L. M. (1994). Urine of reproductively female rainbow trout, Oncorhynchus mykiss (Walbuam), contains a priming pheromone which enhances plasma levels of sex steroids and gonadotropin II in malts. Journal of Fish Biology 44,131-148. 

Peng, C., Humphries, S., Peter, R.E., Rivier, J.E., Blomqvist, A.G. Larhammar, D. (1993) Actions of goldfish neuropeptide Y on the secretion of growth hormone and gonadotropin-II in female goldfish. Gen. Comp. Endocrinol. 90, 306-317. 

Whitten, W. K., 1948, Inactivation of gonadotropins. II. Inactivation of pituitary and chorionic gonadotropins by influenza virus and receptor destroying enzyme, Austr. J. Sci. Res. B 1 388-390. 

Smith, W., Hypothalamic regulation of pituitary secretion of luteinizing hormone. II. Feedback control of gonadotropin secretion, Bulletin of Mathematical Biology, Vol. 42, No. 1, 1980, pp. 57-78. 

Harwood JP, Clayton RN, Chen IT, Knox G, Catt KJ (1980) Ovarian Gonadotropin-Releasing Hormone Receptors. II. Regulation and Effects on Ovarian Development. Endocrinology 107 2 414-421... 

The ovaries perform two major functions (i) the storage, maturation, and expulsion of healthy haploid germ cells (i.e., oocytes) for fertilization, and (ii) the synthesis and secretion of hormones to prepare the reproductive tissues for the establishment and maintenance of pregnancy, to properly regulate gonadotropin secretion from the hypothalamic-pituitary axis, to induce appropriate sexual behaviors, and to provide lactation. The two primary functional units in the ovaries are the maturing follicles and the corpora lutea. 

Gonadotropin- GnRH I and II 10-residue peptide Stimulate the Solid-phase... 

STN24 Welch, C. and Nadkami, S. (1991). Evaluation of the Stratus II immunoassay system for thyroxine, thyroid stimulating hormone, and human chorionic gonadotropin. Clin. Chem. 37, 1041-1042, Abstr. 627. 

Wheeler M, D Souza A, Horn A. Evaluation of test kits for gonadotropins. Lancet 1989 ii 616-17. 

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