THE ROLE OF GLUCOSE AND ACETATE IN THE OXIDATIVE METABOLISM OF THE TESTIS AND EPIDIDYMIS OF THE RAM

Abstract
A general procedure for studying the oxidative metabolism of substrates by specific tissues is described with particular reference to the metabolism of glucose and acetate by the testis and epididymis of the anesthetized ram. Continuous infusion of NaHC14O3 demonstrated the presence of HCO3 pools in testicular and epididymal tissue. Equilibrium conditions between HCO3 pools in the whole sheep were reached within about 300 minutes after the start of infusion. Glucose is a more important metabolite than acetate in testicular and epididymal metabolism, values for glucose and acetate uptake from blood based on arteriovenous differences being 5.0 and 3.0 (imoles/minute/100 g of tissue respectively. The contributions of glucose and acetate to the overall oxidative metabolism of the testis and epididymis calculated by comparing the specific radioactivities of CO2 produced by the tissue with those of the substrates in the circulation were 30 and 20% respectively. About one-third of the glucose and all of the acetate taken up from blood by the testis and epididymis was directly oxidized.