Energy metabolism of normal and lonidamine-treated Sertoli cells of rats.

The effect of lonidamine on oxygen consumption, aerobic lactate production, and [U-14C]glucose metabolism of rat Sertoli cells was investigated. The results may be summarized as follows: (1) Sertoli cells show well-developed energy metabolism both in vitro and in vivo. (2) The rate of aerobic lactate production is markedly higher than in other cell types, either normal differentiated or neoplastic, such as Ehrlich ascites tumor cells. (3) Lonidamine does not affect respiration and aerobic glycolysis of Sertoli cells. This finding is consistent with previous data which demonstrated that the antispermatogenic effect can be mainly ascribed to an irreversible alteration of germ cell mitochondria induced by 1-substituted indazole-3-carboxylic acids of which lonidamine represents one of the most potent derivatives. (4) The functional impairment induced by lonidamine on rat Sertoli cells cannot be ascribed to an action on the energy metabolism even if, up to date, the biochemical target is still unclear.