Absence of LHRH effect on testosterone production by Leydig cells from fetal mouse testis

The effect of LHRH and one of its agonist (des-gly10 (D-Ala6)-LHRH-ethylamide) on the functional activity (testosterone and progesterone production) of purified fetal mouse Leydig cells was examined in short-term primary culture and under dynamic conditions. The continuous presence of increasing concentrations of LHRH (10(-10) to 10(-6) M) for 3 days was unable to affect the hCG-stimulated testosterone production on any day of culture. Stimulated testosterone production progressively decreased from day 1 to day 3 of culture (P less than 0.001). Progesterone accumulation increased in both basal and hCG stimulated conditions during the same period (P less than 0.001) and was not altered by the presence of LHRH at all three concentrations tested. There was no effect of LHRH pretreatment either on the basal production or on the acute hCG stimulation studied during a subsequent 6 h incubation. Exposure of cells to hCG for 120 min enhanced testosterone accumulation. No change in kinetic characteristics was observed when LHRH (10(-6) M) was continuously present in the medium. These results show that LHRH does not have any detectable effect on the fetal population of Leydig cell in the mouse.