4.3. Experimental Design

To analyze the neuroprotective effect of Val, we used an established chronic rotenone paradigm which represents one of the most stable toxin based PD models. Rotenone (2.5 mg/kg) preparation were described in detail previously [46]. Pharmacological effects of Val in vivo were examined using the following treatment groups (n = 15). Group I (control) received intraperitoneal injection of myglol and olive oil which are vehicles for rotenone and Val respectively which served as control group. Group II (rotenone) received intraperitoneal injection of rotenone (2.5 mg/kg) once daily for 4 weeks and served as experimental PD model. Group III (rotenone+ Val): Immediately before treatment, Val (40 mg/kg, i.p) was prepared and administered once daily for four weeks, 30 min prior to ROT administration. Dosage fixed for Val was based on previous study [40]. Group IV received only intraperitoneal injection of Val (40 mg/kg, i.p) once daily for four weeks and served as drug control. Body weight of experimental animals were obtained every 5 days for a total period of 4 weeks.