[Effect of starvation on the metabolism of the xenobiotic p-nitroanisole in isolated hepatocytes of rats of both sexes].

Hepatocytes isolated from fed female rats are characterized by the lower contents of cytochrome P-450 and more slowly metabolize the xenobiotic p-nitroanisole (p-NA) than hepatocytes from males. The starvation does not change the cytochrome P-450 contents, but depresses the p-NA biotransformation. The inhibition of p-NA O-demethylation capacity is a result of insufficiently reduced equivalent supply, because the addition of exogenous NADPH to the cells with digitonin-permeabilized plasma membrane increases p-nitrophenol (p-NPh) formation. In the presence of exogenous NADPH hepatocytes from fasting male and female rats produce more p-NPh, than those from fed ones. That suggests the induction of xenobiotic biotransformation system during starvation. Sex differences in response of xenobiotic biotransformation system to starvation manifest themselves in different ratio in contents of free and conjugated p-NPh.