Morphometry of abnormal peroxisomes induced by withdrawal of bezafibrate, a hypolipidemic drug in male rat hepatocytes.

Peroxisomes containing fibrillar structures were induced after 1 week withdrawal of bezafibrate, a peroxisome proliferator. In this report, the relation between the duration of bezafibrate treatment and the induction of abnormal peroxisomes in rat hepatocytes was studied morphometrically. The abnormal peroxisomes did not appear during 3 to 90 days of treatment with bezafibrate, but they appeared after 1 week withdrawal of it. The number and frequency of abnormal peroxisomes were prominent in 3, 7, and 14 days of treatment followed by 1 week of withdrawal of bezafibrate. It was evident that the frequency of abnormal peroxisomes decreased with 30-90 days administration of bezafibrate. This means that long-term (30-90 days) treatment with bezafibrate suppresses the induction of abnormal peroxisomes.