Ontogenesis of hepatocyte respiration processes in relation to rat liver cytochrome P450-dependent monooxygenase system.

The study aimed to evaluate the effect of age on the activity of the cytochrome P450-dependent monooxygenase system and on cellular respiration processes in Wistar rats aged 0.5, 1, 2, 4, 8, 12, 20, and 28 months. The following parameters were determined: cytochrome P450 content, cytochrome b5 content, NADPH-cytochrome P450 reductase activity, and NADH-cytochrome b5 reductase activity, succinate dehydrogenase (SDH) activity, and lactate dehydrogenase (LDH) activity. In the study, cytochrome P450 content increased in the first month of life, which was accompanied by increases in SDH and LDH activities. In the subsequent months, SDH activity decreased, whereas LDH activity increased to reach the maximum in month eight and then decreased. Cytochrome b5 content showed a decreasing tendency throughout the experiment. NADH-cytochrome b5 reductase activity showed only slight deviations in individual age groups.