Purpose:Although there are clinical data on the coexistence of epilepsy and Parkinson's disease (PD) in literature, this interaction has not been studied experimentally. The administration of 6-hydroxydopamine (6- OHDA) to nigrostriatal pathway is one of the common experimental animal models of PD. In this model apomorphine-induced rotation test can be used to evaluate the degree of motor deficit. Present study evaluated relation between body weight change (BWC) and the degree of neurodegeneration in Genetic Absence Epilepsy Rats from Strasbourg (GAERS).

Method: According to injection site, 30-days old GAERS (15 male) were divided into 2 groups: Striatum (n=6) and medial forebrain bundle (MFB) (n=9). GAERS were stereotaxically injected unilaterally with 8 μg/4 μL 6- OHDA per location. Injections were performed at two locations for striatum lesion (AP:-0.5, ML:3.0, DV:6; AP:- 1, ML:3.0, DV:6) and one for MFB (AP:-1.4, ML:1.6, V:7.1). Three weeks later, rotation test was performed with 0.05 mg/kg subcutaneous apomorphine. Rotation was counted for 30 minutes. Rats were weighed before 6- OHDA injection (first measurement) and rotation test (second measurement). BWC was calculated as [(second measurement-first measurement)/first measurement]x100. Data were expressed as mean±standard error of mean and analyzed with Pearson Correlation test by using GraphPad Prism. Statistical significance was set at p<0.05.

Result: BWC was %81.5±6.95 and rotation count was 153±51 in the striatum group while BWC was %91.6±4.28 and rotation count was 252±40 in the MFB group. There was statistically significant negative correlation between BWC and rotation counts in striatum group (r=-0.89; p=0.017) while there was low negative correlation in MFB group (r=-0.48; p=0.191). The correlation in MFB group was not statistically significant, but had moderate effect size (0.3<r<0.5) 

Acknowledgment: Supported by TUBITAK-SBAG-218S653.