Effect of anti-relapse antimalarial compound CDRI 80/53 and primaquine on hepatic mixed function oxidase system of rhesus monkey

A potential anti-relapse antimalarial compound CDRI 80/53 [N¹-(3-acetyl-4-5-dihydro-2-furanyl)-N⁴-(6-methoxy-8-quinolinyl)1,4-pentanediamine] at 7.5 mg/kg body weight and primaquine at 6.0 mg/kg body weight did not cause any significant change in the status of hepatic microsomal mixed function oxidase system of rhesus monkeys, when given orally for 7 days. Further, the extension of the treatment at the same dossier up to 21 days resulted in impairment of the different indices of the MFO system. The compound CDRI 80/53 inhibited cytochrome P-450, aminopyrine-N-demethylase, aniline and benzo(a)pyrene hydroxylases, cytochrome b₅ and haem levels by 17, 11, 58, 0, 36 and 35% whereas the inhibition caused by primaquine was 34, 40, 72, 54, 39 and 38% respectively, establishing that the cytochrome P-450 dependent mono-oxygenase system of monkey liver was comparatively less suppressed by compound CDRI 80/53. The cessation of the compound/drug treatment resulted in almost complete reversal of all the MFO activities to normal in a period of about 6 weeks.