Fine structural observations on the rat hepatocytes after repeated treatment of cyclosporin A

Cyclosporin A 반복투여후 랫드 간세포의 미세구조적 관찰

This study was carried out to investigate the fine structural changes of rat hepatocytes by repeated treatment of cyclosporin A that has been widely used for immunosuppressive drug in organ transplantation. Sprague-Dawley rats were kept in experimental circumstances for 2 weeks and 50mg/kg B.W of cyclosporin A was injected once a day subcutaneously for 7 days and sacrificed at 1 hour, 1 day, 3 days, 7 days, 14 days, 28 days after the last injection. Fine structural changes were observed by transmission electron microscope (JEM 1200EX II) and the results obtained were as follows. 1. Accumulation of lipid droplets in hepatocytes was prominently increased in 1 hour and 1 day lapse groups, and this finding was slightly reduced in 3 days lapse group and remarkably reduced from 7 days lapse group enough to be recovered completely in 14 days lapse group. 2. Dilatation of rough endoplasmic reticule cisternae, detachment of membrane bound ribosomes, proliferation of smooth endoplasmic reticula were observed in 1 hour and 1 day lapse groups, and these findings were mild in 3 days lapse group and abruptly reduced from 7 days lapse group enough to be recovered completely in 28 days lapse group. 3. Small myelin figures were observed in 3 days lapse group after CsA-treatment. 4. Swelling of mitochondria and destruction of their cristae were observed in 1 hour and 1 day lapse groups, and these findings were recovered from 3 days lapse group. 5. Dilatation of bile canaliculi and remarkable loss of microvilli in the pericanalicular wall were observed in 1 hour lapse group and the most severe change was shown in 1 day lapse group and lasted to 3 days lapse group, and these findings were reduced gradually from 7 days lapse group enough to recovered completely in 28 days lapse group.