Effects of hormones on adult frog (Rana pipiens) testes in organ culture

Abstract

AbstractTestes from adult Rana pipiens were maintained for five days in organ culture in a chemically defined medium consisting of CulturSTAT 199 organics dissolved in amphibian Ringer's solution. Various steroid hormones and vitamins, when added individually to testicular organ cultures, were found to be toxic. Toxicity of these substances was reduced or abolished by the simultaneous addition of protein hormones. Most combinations of protein hormones resulted in improved maintenance of cultured testes over that obtained in hormone‐free media. The combinations FSH + LH, and FSH + LH + insulin + testosterone, resulted in almost complete testicular maintenance in vitro and, in some circumstances, even stimulation of spermatogenesis. However, in no case were secondary spermatocytes maintained in these organ cultures, and spermatogenesis could be stimulated only through the first meiotic division.Testosterone, previously demonstrated in vivo to inhibit spermatogenesis at the secondary spermatogonial level, exerted no such inhibitory action in vitro. At the dose level used, testosterone appeared to have a slightly deleterious, but nonspecific, effect on testicular maintenance.Seasonal variations in the sensitivity of the testis to hormones and other conditions in vitro were noted. Testicular maintenance was relatively poor, even in hormone‐supplemented media, during the period of active spermatogenesis (summer). In contrast, gonadotropin‐induced stimulation of spermatogenesis in vitro occurred only in testes taken from winter frogs, at a time when the testicular epithelium is presumed to be maximally sensitive to gonadotropic action.