title: Regulation of renin angiotensins by gonadotropic hormones in cultured murine Leydig tumor cells. Release of angiotensin but not renin.
abstract: Renin and angiotensins coexist in various tissues. The mode of control of the extrarenal renin-angiotensin system is not clear. Whether it is renin or angiotensin that is secreted has not been identified. We have investigated gonadotropin-dependent synthesis and subsequent release of the components of the intracellular renin-angiotensin system in a cloned and cultured mouse Leydig tumor cell line (MA-10). Treatment of cultured Leydig cells with bovine luteinizing hormone (bLH, 100 ng/ml) or human chorionic gonadotropin (hCG, 25 ng/ml) resulted in greater than 150- and 40- fold increased formation of angiotensin I and angiotensin II. In cells incubated with bLH or hCG, the majority of AII (up to 90%) was found in the culture medium while most of angiotensin I (greater than 85%) was in the cell lysate. Treatment with gonadotropic hormones (bLH/ hCG) increased renin 35- to 40-fold. Renin activity was confined mainly in the cell lysate even after the stimulation by gonadotropins, and only 1-2% of the total renin activity was detectable in culture medium. These results were interpreted that, in these transformed cells, hormonally-induced renin functions to generate angiotensin I within the Leydig cell and it is the angiotensins which are secreted.
mesh_terms: D000803:Angiotensin I / Q000378:metabolism; D000804:Angiotensin II / Q000378:metabolism*; D000805:Angiotensin III / Q000378:metabolism; D000818:Animals; D002478:Cells, Cultured; D006063:Chorionic Gonadotropin / Q000494:pharmacology; D002851:Chromatography, High Pressure Liquid; D007984:Leydig Cell Tumor / Q000378:metabolism*; D007986:Luteinizing Hormone / Q000494:pharmacology; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D011863:Radioimmunoassay; D012083:Renin / Q000378:metabolism*; D013736:Testicular Neoplasms / Q000378:metabolism*; D013997:Time Factors
chemical_list: D006063:Chorionic Gonadotropin; D000804:Angiotensin II; D000805:Angiotensin III; D007986:Luteinizing Hormone; D000803:Angiotensin I; D012083:Renin