The Effects of Steroid and Gonadotrophic Hormones in Vitro on the Metabolic Activity of Normal and Cryptorchid Rat Testicular Tissues

Experiments were conducted to determine the effects of in vitro treatment with testosterone propionate, estradiol benzoate, luteinizing hormone, or follicle-stimulating hormone on respiration, glucose uptake, and lactic acid accumulation by testis tissue from normal and cryptorchid rats. The tissues were incubated at 33.5 C (testis temperature) and 37.5 C (body temperature) in a modified Locke’s solution containing 5.5 × 1O−5m glucose. The in vitro oxygen consumption, carbon dioxide production, and glucose uptake of 2- and 8-day cryptorchid testis tissues were about 50% lower than those of normal testis tissue. Lactic acid accumulation of the cryptorchid testicular tissues was not significantly different from that of normal testis tissue. In vitro treatment with testosterone propionate and luteinizing hormone depressed significantly all the metabolic parameters studied, whereas estradiol benzoate and folliclestimulating hormone (in low concentrations) stimulated the oxidative metabolic activity of both normal and cryptorchid testis tissues. No consistent temperature effects were noted in the experiments with the various hormones.