Placental growth hormone

Chorionic Somatomammotropin. Three genes encode human chorionic somatomammotropin [11085-36-2] (hCS). These are located within a cluster of genes on human chromosome 17 which code for pituitary growth hormone [12629-01 -5] (GH-N), placental GH [109675-94-7J (GH-V), and three hCS molecules, ie, hCS-A, hCS-B, and hCS-V (1 3), also referred to as human placental lactogens. All of these molecules ate closely related to GH in stmcture (Fig. 1). Placental lactogens also exist in rodents and mminants however, these hormones are more closely related to prolactin than GH. 

Fig. 1. Primary stmcmre of the human growth hormone family of proteins. GH-N = pituitary GH GH-V = placental GH variant ...

Knockout of the prolactin receptor, rather than knockout of prolactin, is necessary to explore the role of the hormone and its receptor in maternal behavior because several molecules other than prolactin, including growth hormone (GH) and placental lactogens, may stimulate the prolactin receptor. Disruption of the prolactin receptor gene in a mouse model has allowed for assessment of phenotypes associated with partial and complete prolactin receptor deficits (Goffin et ah, 1999). Prolactin receptor knockout mice have severe reproductive deficits. Heterozygous mothers (receptor —/+) were also unable to lactate (Bridges, 1998). 

Goffin, V., Shiverick, K. T., Kelly, P. A., and Martial, J. A. (1996). Sequence-function relationships within the expanding family of prolactin, growth hormone, placental lactogen, and related proteins in mammals. Endocrine Reviews 17, 385—410. 

M. L. Hogan, et al. Sequence of the pituitary and placental lactogenic and growth hormones evolution from a primordial peptide by gene reduplication. Proc. Natl. Acad. Set U.S.A. 68, 866 (1971).]... 

Trophoblastic expression was evaluated for hCG and its derivatives, leutenizing hormone (EH, LH 3), follicle stimulating hormone (FSH, FSH 3), placental lactogen (PL), and growth hormone (GH-227) in 40 neuroendocrine lung neoplasms, 29 primary pulmonary adenocarcinomas, 20 squamous cell carcinomas, and 1 adenosquamous carcinoma.Trophoblastic hormone immunoreactivity was found in 28 of 90 (31%) of all lung carcinomas but primarily in typical carcinoids. 

Human placental lactogen (HPL) is a 22-kD protein with partial homology to growth hormone. HPL is secreted by syncytiotrophoblastic cells in choriocarcinoma and intermediate trophoblasts in a testicular trophoblastic tumor that is a counterpart to a uterine placental site trophoblastic tumor. 

Forsyth IA. Variation among species in the endocrine control of mammary growth and function the roles of prolactin, growth hormone and placental lactogen. J Dairy Sci... 

Herman, A., Helman, D., Livnah, O., and Gerder, A. (1999). Ruminant placental lactogens act as antagonists to homologous growth hormone receptors and as agonists to human or rabbit growth hormone receptors./. Biol. Chem. 274, 7631-7639. 

Mannik J, Vaas P, Rull K, Teesalu P, Laan M. Differential placental expression profile of human growth hormone/chorionic somatomammotropin genes in pregnancies with pre-eclampsia and gestational diabetes mellitus. Mol Cell Endocrinol. 2012 355 180-7. 

Wallis, M. The molecular evolution of pituitary growth hormone, prolactin and placental lactogen a protein family showing variable rates of evolution. J. Mol. Evol. 16, 10-18 (1981) Zahner, H., Drautz, H., Weber, W. Novel approaches to metabolite screening. In Bioactive Microbial Products Search and Discovery (J. D. Bu Lock, L, J, Nisbet. D. J. Winstanley, eds,), pp. 51-70. Spec. Publ. Soc, Gen. Microbiol. 6, Academic Press, New York 1982... 

Thus far, to the extent that our observations include the same parameters as those published, PPP(H) appears to be identical with the "human placental lactogen", "chorionic growth hormone-prolactin" and "placental protein". 

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