VITAMIN-E PRETREATMENT PREVENTS CYCLOSPORINE-A-INDUCED CRYSTAL DEPOSITION IN HYPEROXALURIC RATS

The in vivo effect of cyclosporin A (CsA) on renal calcium oxalate (Ca Ox) crystal retention in experimental hyperoxaluric rats was investiga ted, Further, the effect of pretreatment of vitamin E on the above con ditions was also studied, Male Wistar rats were divided into two major groups each containing 40 rats, One of the groups was pretreated with vitamin E, Both major groups were then subgrouped into four groups: g roup 1 received the vehicle (olive oil); group 2 received CsA in olive oil (50 mg/kg); group 3 received 3% ammonium oxalate (AmOx), and grou p 4 received CsA + AmOx, Nephrotoxicity was assessed by the activities of urinary marker enzymes and also by histopathology, Urinary oxalate excretion as well as the activities of lactate dehydrogenase, gamma-g lutamyltranspeptidase, alkaline phosphatase and inorganic pyrophosphat ase enzymes were elevated either in CsA-alone or AmOx-alone treated gr oups, On combined administration of both CsA and AmOx, further elevati ons of these enzymes were observed, Urinary excretion of oxalate conce ntration positively correlated with urinary excretion of these enzymes , Deposition of CaOx crystals was seen only in the kidneys of rats tha t received combined treatment, On pretreatment with vitamin E the obse rved increased urinary activities of the enzymes and oxalate, histopat hological changes and the deposition of CaOx crystals by administratio n of CsA in hyperoxaluria were prevented suggesting that vitamin E cou ld be supplemented to prevent CsA-induced membrane damage.