title: Effects of seminiferous tubule secreted factor(s) on Leydig cell cyclic AMP production in mature rat.
abstract: The effects of spent media from seminiferous tubules (STM) on Percoll-purified rat Leydig cells were investigated. Intracellular and extracellular cyclic AMP (cAMP) accumulation and testosterone production were measured. After a 5 h incubation period, STM reduces both the basal and LH-dependent cAMP levels (38 and 20%, respectively for intra- and extracellular cAMP) while, simultaneously, a stimulation of testosterone production is observed (47 to 50%, respectively in the absence or presence of LH). The reduction of cAMP levels observed after 5 h is likely to be due to the potentiating effect of the STM factor on the LH-dependent initial rise of the cAMP level which, in turn, induces a desensitization of the Leydig cell adenylate cyclase. This substance is a thermolabile protein (Mr greater than 50 000) produced by the Sertoli cell, independent of FSH and testosterone controls, and different from the LHRH-like substance.
mesh_terms: D000818:Animals; D000242:Cyclic AMP / Q000096:biosynthesis*; D007987:Gonadotropin-Releasing Hormone / Q000031:analogs & derivatives / Q000037:antagonists & inhibitors / Q000494:pharmacology; D066298:In Vitro Techniques; D007985:Leydig Cells / Q000378:metabolism*; D007986:Luteinizing Hormone / Q000494:pharmacology; D008297:Male; D011761:Pyrrolidonecarboxylic Acid / Q000031:analogs & derivatives; D051381:Rats; D011919:Rats, Inbred Strains; D012671:Seminiferous Tubules / Q000502:physiology*; D013737:Testis / Q000502:physiology*; D013739:Testosterone / Q000096:biosynthesis
chemical_list: D007987:Gonadotropin-Releasing Hormone; D013739:Testosterone; C010661:surfagon; C034511:LHRH, pGlu(1)-Phe(2)-Trp(3,6)-; D007986:Luteinizing Hormone; D000242:Cyclic AMP; D011761:Pyrrolidonecarboxylic Acid