Effects of chicken and ovine luteinizing hormone on androgen release and cyclic AMP production by isolated cells from the quail testis

Abstract

Cellular suspensions were prepared from mature quail testes using collagenase. Approximately 30% of the cells could be identified as Leydig cells. The addition of chicken or ovine luteinizing hormone (LH) greatly increased androgen (testosterone plus any dihydrotestosterone_ release and log-linear responses were obtained. The minimally effective doses of chicken LH (AE 1) and ovine LH (NIH LH-S18) were about 2 and 4 ng, respectively. An antiserum to chicken LH blocked the effects of chicken but not of ovine LH. LH had no effect on the low levels of testosterone released by isolated seminiferous tubules. The action of LH was potentiated 1.5- to 3-fold in the presence of phosphodiesterase inhibitors such as 1-methyl-3-isobutyl xanthine or theophylline. Cyclic AMP stimulated testosterone release and a dose-response curve was established for dosages between 2.5 and 60 m M per tube. Chicken LH increased cyclic AMP formation in the isolated interstitial cells within 5 min of adding a large dose; the first signs of enhanced testosterone release were not detectable until 30 min had elapsed. A dose-response relationship existed between chicken LH and cyclic AMP formation although the minimally effective dose was 125 ng. Cycloheximide inhibited LH-induced testosterone release but not the rise in intracellular cyclic AMP formation. Actinomycin D reduced both the testosterone and cyclic AMP responses to LH.