Luteinising hormone

Follicle Stimulating Hormone (FSH, foilitropin) [9002-68-0] Mr 36,000. Purified by Sephadex GlOO gel filtration followed by carboxymethyl-cellulose with NH4OAC pH 5.5. The latter separates luteinising hormone from FSH. Solubility in H2O is 0.5%. It has an isoelectric point of 4.5. A soln of Img in saline (lOOmL) can be kept at 60° for 0.5h. Activity is retained in a soln at pH 7-8 for 0.5h at 75°. The activity of a 50% aq EtOH soln is destroyed at 60° in 15 min. [Bloomfield et al. Biochim Biophys Acta 533 371 1978 Hartree Biochem J100 754 1966 Pierce and Parsons Ann Rev Biochem 50 465 1981.]... 

Most GPCRs interact with and activate more than one G-protein subfamily, e.g., with Gs plus Gq/n (histamine H2, parathyroid hormone and calcitonin recqrtors), Gs plus G (luteinising hormone receptor, 32-adrenoceptor) or Gq/11 plus G12/13 (thromboxane A2, angiotensin ATb endothelin ETA receptors). Some receptors show even broader G-protein coupling, e.g., to Gi, Gq/n plus Gi n ( protease-activated receptors, lysophosphatidate and sphingosine-1-phosphate receptors) or even to all four G-protein subfamilies (thyrotropin receptor). This multiple coupling results in multiple signaling via different pathways and in a concerted reaction of the cell to the stimulus. 

Bronson F. and Maruniak J.A. (1976). Differential effects of male stimuli on follicle stimulating hormone, luteinising hormone and prolactin secretion in prepubertal female mice. Endocrinology 98, 1101-1108. 

Mackay-Sim, A. and Rose, J.D. (1986) Removal of vomeronasal organ impairs lordosis in female hamsters effect is reversed by luteinising hormone-releasing hormone. Neuroendocrinology 42, 489-493. 

Hoitink, M. A., Hop, E., Beijnen, J. H., Bull, A., Kettenes-van den Bosch, J. J., and Underberg, W. J. M. (1997). Capillary zone electrophoresis mass spectrometry as a tool in the stability research of the luteinising hormone-releasing hormone analogue goserelin.. Chromatogr. A 776, 319—327. 

FSH - follicle-stimulating hormone GnRH - gonadotrophinreleasing hormone LH - luteinising hormone. 

Biochemistry provides the explanation for Porter s observations a decrease in the plasma concentration of testosterone could account for the inability to perform whilst die reduced extent of feedback inhibition on die pituitary would lead to an increased rate of secretion and hence an increase in die blood concentration of luteinising hormone, which has been claimed to increase the degree of sexual arousal in men. 

Follicle-stimulating hormone, luteinising hormone Follicle-stimulating hormone, luteinising hormone... 

Figure 19.11 Hormones secreted by the hypothalamus, anterior pituitary, ovary and testis and feedback regulation. GnRH is gonadotrophin-releasing hormone the gonadotrophins are follicle-stimulating hormone (FSH) and luteinising hormone (LH). The effect of these hormones on activities in the ovary and testes is shown. FSH stimulates synthesis and secretion of oestradiol from follicle, and spermatogenesis in testis. LH stimulates synthesis and secretion of progesterone from corpus luteum and synthesis and secretion of testosterone by the Leydig cells.

Luteinising hormone (LH) or interstitial cell stimulating hormone (ICSH). 

Purified extract of human postmenopausal urine containing follicle stimulating hormone (FSH) and luteinising hormone (LH) is known as human menopausal gonadotrophin. The relative in vivo activity is designated as a ratio, the 1 1 ratio is also known as menotrophin. 

Inhibiting ovulation by blocking the release of follicle stimulating hormone and luteinising hormone from the anterior lobe of pituitary gland. 

Muller T, Simoni M, Pekel E, et al. Chorionic gonadotrophin beta subunit mRNA but not luteinising hormone beta subunit mRNA is expressed in the pituitary of the common marmoset Callithrix jacchus). J Mol Endocrinol 2004 32(l) 115-28. 

The pituitary gland is then dissected out and stored separately. There are numerous publications which refer to the measurement of luteinising hormone releasing hormone (LHRH - Adams and Spies 1981a-c, Aubert et al. 1980, Berault et al. 1983, Catt et al. 1980, Chan et al. 1981, Clayton 1982a,b, Clayton and Catt... 

Anabolic Steroids in Humans There are several methods to indicate that testosterone has been administered to a male human. Natural testosterone production is controlled by a feedback mechanism involving the pituitary gland, and administration of testosterone will suppress the natural production of pituitary hormones such as luteinising hormone (LH) and follicle stimulating hormone (FSH). 

Prostatic cancer is androgen-dependent and metastatic disease can be helped by orchidectomy, or by a gonadorelin analogue, e.g. buserelin, goserelin, leuprorelin or triptorelin. These cause a transient stimulation of luteinising hormone and thus testosterone release, before inhibition occurs some patients may experience exacerbation of tumour effects, e.g. bone pain, spinal cord compression. Where this can be anticipated, prior orchidectomy or antiandrogen treatment, e.g. with cyproterone or flutamide, is protective. 

Chorionic gonadotrophin (human chorionic gonadotrophin HCG) is secreted by the placenta and is obtained from the urine of pregnant women. Its predominant action is that of luteinising hormone (LH) (interstitial cell stimulating hormone) which induces progesterone production by the corpus luteum and, in the male, gonadal testosterone... 

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