Leydig’s cells

Luteinizing hormone/ Truncated TM5 Leydig s cell Constitutively (77-79)... 

Metyrapone is useful in testing the endocrine functioning of the a cells of pancreatic islets P cells of pancreatic islets Neurohypophysis Pituitary-adrenal axis Leydig s cells of the testes... 

The interstitial cell-stimulating hormone of the hypophysis controls the production of gonadal hormones. In the testes, Leydig s cells are stimulated to produce testosterone and estrone in the female organism the follicles are stimulated to produce progesterone (see also Section 11). 

Tfelt-Hansen, J., Ferreira, A., Yano, S., Kanuparthi, D., Romero, J. R., Brown, E. M. and Chattopadhyay, N., 2005, Calcium-sensing receptor activation induces nitric oxide production in H-500 Leydig cancer cells. Am J Physiol Endocrinol Metab 288, E1206-13. 

Decreases in sperm motility and increased acid phosphatase activity were reported to result from oral administration of 0.05 mg/kg lead in drinking water to male rats for 20-30 days in a study from the former U.S.S.R. (Krasovskii et al. 1979). Dystrophic changes of the Leydig cells were reported in gonadal tissues of rats exposed to doses as low as 0.005 mg lead/kg/day. The weaknesses of the study include absence of data on the strain and number of rats used, and the fact that PbB levels were not reported. 

Neaves, W. B., Johnson, L., Porter, J. C., Parker, C. R. and Petty, C. S. (1984). Leydig cell numbers, daily sperm production, and serum gonadotropin levels in aging men. Journal of Clinical Endocrinology and Metabolism 59, 756-763. 

Piper WN, Ruangwises S, Bestervelt LL, et al. 1991. Leydig cell testosterone production and P45017 (17-hydroxylase and C17-201yase) activities after in vitro exposure to... 

Data on the toxicity of HFC-134a indicate that it is nontoxic in most circumstances. Most of the changes reported have been at high concentrations, which also induce narcosis. There is no evidence of genetic toxicity for HFC-134a. The primary effect reported is the induction of Leydig cell hyperplasia and adenomas in male rats exposed at 50,000 ppm for 6 h/d, 5 d/wk over a 2-yr period (Collins et al. 1995 Hext and Parr-Dobrzanski 1993). The NOAEL of 10,000 ppm from these data was the basis of the EPA s RfC. 

T. H. Fong, S.M. Wang, and H.S. Lin, Immunocytochemical demonstration of a lipid droplet-specific capsule in cultured Leydig cells of the golden hamsters, J. CeU. Biochem., 1996, 63, 366-373. 

Inhibin A is also a sensitive marker of Sertoli cell differentiation (>90% positive). Sertoli cell tumor including its large cell calcifying variant stains variably positive with antibodies to vimentin, cytokeratin, S-100, synaptophy-sin, chromogranin, and neuron-specific enolase. Cytokeratin immunoreactivity in Sertoli cell tumors is usually stronger than that seen in Leydig cell tumors. Immunoreactivity for FLAP is not seen in Sertoli cell tumors. 

Gagnon S, Tetu B, Silva EG, et al. Frequency of alpha-fetoprotein production by Sertoli-Leydig cell tumots of the ovary An immunohistochemical study of eight cases. Mod Pathol. 1989 2 63-67. 

Murakami M, Hosokawa S, Yamada T, Harakawa M, Ito M, Koyama Y, Kimma J, Yoshitake A, Yamada H (1995) Species-specific mechanism in rat Leydig cell tumori-ogenesis by procymidone. Toxicol Appl Pharmacol 131 244-252 Clegg ED, Cook JC, Chapin RE, Foster PM, Daston GP (1997) Leydig cell hyperplasia and adenoma formation Mechanisms and relevance to humans. Reprod Toxicol 11 107-121... 

Prentice DE, Siegel RA, Donatsch P, Qureshi S, Ettlin RA (1992) Mesulergine induced Leydig cell tumours, a syndrome involving the pituitary-testicular axis of the rat. Arch Toxicol 15 197-204... 

Ramnath, H. I., Peterson, S., Michael, A. E., Stocco, D. M., and Cooke, B. A. (1997). Modulation of steroidogenesis by chloride ions in MA-10 mouse tumor Leydig cells roles of calcium, protein synthesis, and the steroidogenic acute regulatory protein. Endocrinology 138, 2308-2314. 

Berg, A.M., A.B. Kickman, E. Miao, A. Cochran, S.R. Wilson, and WH. Orme-Johnson (1990). Effects of inhibitors of cytochrome P-45017a on steroid production in mouse Leydig cells and mouse and pig testes microsomes. Biochemistry 29,2193-2201. 

L.S. Jefferson et al. (1981). The pituitary-testicular axis in the streptozotocin diabetic male rat Evidence for gonadotroph, Sertoli cell and Leydig cell dysfunction. Int. J. Androl. 4, 265-80. 

These cells arise from interstitial mesenchymal tissue between the tubules during the eighth week of human embryonic development. They are located in the connective tissue between the seminiferous tubules, Leydig cells are the endocrine cells in testis that produce testosterone from cholesterol via a serie.s of enzymatic pathways and steroidal intermediates under the control of luctinizing hormone (LH) from pituitary. The effects of testosterone can be grouped into the following categories ... 

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