Abstract: AIM: To investigate developing cerebel-lum with long-term orally phenytoin zinc(PZ)orpheny-toin sodium(PS)in the childhood rabbits.METHODS: One-month-old young rabbits were taken PZ orPS orally for7 months(doses:30 and 10 mg·kg^-1·d^-1).The rab-bits were performed forCT scans before,during and afteradministrated.Taken drugs end,brains were fixed with Brouin' s pourfrom carotid,separated and determined weight and width,length and height of the brain.RESULTS: In the high-dose grouPtreated with PS,at the 4 and 7 months crosscut of cerebellum were decreased by 14.0%(P<0.05)and 32.2%(P<0.01)and crosscut of vermis were decreased by 16.4%(P<0.05)and 30.8%(P<0.01)respectively compared with the control with CT scan analysis.In PZ high-dose grouPonly at 7months,crosscut of cerebellum and vermis were decreased by 16.1%(P<0.05)and 19.7%(P<0.01),respectively compared with the control by CT.In PS high-dose grouPthe width and length of fixed cere-bellum and vermis were more short than control,the wet weight and dehydrated weight with ethanol of the whole brain were decreased than control,the weight of whole brain and cerebellum was decreased by 15.4% and 18.4%respectively compared with control.Nevertheless in PZ grouPabove-mentioned determine were no differ-ence with control.CONCLUSION: Long-term use of PS may cause cerebellaratrophy in child rabbit,while PZ may lowerthe cerebellaratrophy.

Key words: phenytoin zinc, phenytoin sodium, CT scans, cerebellum, childhood rabbit