Gossypol modulation of mouse heart and liver lactate dehydrogenase isoenzymes as a function of gender.

Acute treatment with gossypol produced both tissue specific and sex-dependent alterations of M and H subunits of mouse lactate dehydrogenase. Gossypol induced female mouse heart cytoplasma H subunit and inhibited both enzyme subunits in the male mouse. Gossypol induced mouse liver mitochondrial lactate dehydrogenase subunit M in both sexes 50 hrs after acute drug administration while was ineffective on the testicular enzyme. Induction of hepatic lactate dehydrogenase may enhance NADH:NAD ratio, resulting in alteration of cellular redox status and reduction of NAD utilization by other dehydrogenases. The gossypol-mediated sex-dependent changes of heart lactate dehydrogenase isoenzymes may be of value in the prediction of certain aspects of gossypol toxicity.