title: Stimulation of aromatase activity in immature porcine Leydig cells by fibroblast growth factor (FGF).
abstract: The effects of fibroblast growth factor (FGF) on testicular aromatase activity has been studied using primary cultures of porcine Leydig cells. After culture for 3 days in the absence or presence of FGF, the ability of the cells to produce estrogen was examined in a 4h-test period in which either (a) hCG (10(-9) M) or (b) androstenedione (3 x 10(-6) M) was added to the medium. FGF produced a 3- to 20-fold increase in estrogen formation from endogenous or exogenous substrate during the test period, in spite of a marked decrease (approximately equal to 60%) in [125I]-hCG binding and no significant change in testosterone concentration. Stimulation of estrogen secretion by FGF was dose-(ED50 approximately equal to 2 ng/ml) and time-dependent, the first and maximal effects were observed after 12h and 48h, respectively. Preliminary tests with several other factors (insulin, EGF, TGF-beta, FSH and hCG) showed that hCG alone directly stimulated aromatase activity. From these findings a role is suggested for FGF as a paracrine/autocrine agent in the control of estrogen secretion by Leydig cells.
authors.affiliation: INSERM U307, Hopital Debrousse, Lyon, France.
authors.forename: J I
authors.initials: JI
authors.lastname: Raeside
authors.forename: M C
authors.initials: MC
authors.lastname: Berthelon
authors.forename: P
authors.initials: P
authors.lastname: Sanchez
authors.forename: J M
authors.initials: JM
authors.lastname: Saez
mesh_terms: D000818:Animals; D001141:Aromatase / Q000378:metabolism*; D002478:Cells, Cultured; D006063:Chorionic Gonadotropin / Q000494:pharmacology; D004305:Dose-Response Relationship, Drug; D004967:Estrogens / Q000096:biosynthesis*; D005346:Fibroblast Growth Factors / Q000494:pharmacology*; D007328:Insulin / Q000494:pharmacology; D007985:Leydig Cells / Q000187:drug effects / Q000201:enzymology*; D008297:Male; D013552:Swine; D013739:Testosterone / Q000096:biosynthesis
chemical_list: D006063:Chorionic Gonadotropin; D004967:Estrogens; D007328:Insulin; D013739:Testosterone; D005346:Fibroblast Growth Factors; D001141:Aromatase