Experimental research of levodopa dosage and levodopa-induced dyskinesia

Objective To ohaerve the behavior of PD rat models treated with different dosages of levodopa and analyze the relation- ship between levodopa - induced dyskinesia (LID) and dosage of levedopa. Method The successful PD rat models were set up by 6-OHDA injection into right MFB. Two groups were divided according to the different treatment dosages of levodopa, which were given through perito- neal injection twice a day for 21days. One group was given for 10 mg/kg body weight, the other for 50 mg/ kg body weight. The score of AIM and rotational behavior were observed. Results Among altogether 28 female SD rats, 22 were chosen as the successful PD models and the successful rate arrived at 78. 57%. LID could be induced in both groups, but there were great differences in occurrence and duration time of AIM, AIM score, pharmacodynamic action time, and rotational behavior between these two groups( P<0.05). Conclusions The be- havior of LID has great relationship with the given dosage of levodopa. Key words: Levedopa;  Parkinson disease;  Movement disorders