effects of nigella sativa hydro-alcoholic extract on memory and brain tissues oxidative damage after repeated seizures in rats

ABSTRACT

Regarding the therapeutic properties of Nigella sativa [NS], the effects of the plant hydro–alcoholic extract on learning, memory and brain tissues oxidative damage were investigated in penthylenetetrazole [PTZ]-induced repeated seizures. There were 4 experimental groups including 1- control group; received saline, 2- PTZ group; received saline and PTZ [50 mg/Kg, i.p], 3- PTZ-NS 200 and 4- PTZ-NS 400 ; received 200 and 400 mg/Kg of NS extract respectively, before PTZ injection in 5 consecutive days. Seizure scores were lower in PTZ–NS 200 and 400, furthermore the seizure onset latencies were higher in these groups than PTZ group [P<0.05 and P<0.01]. In Morris water maze, the time spent in target quadrant by PTZ group was lower than control group [P<0.05]; while, 400 mg/Kg of the extract increased it [P<0.01]. In the passive avoidance test, delay time to enter the dark by PTZ group was lower than control at 1 and 24 hours after training [P<0.01 - P<0.001]; while, 400 mg/Kg of the extract increased it [P<0.05]. The total thiol concentration in hippocampal and cortical tissues of PTZ group was reduced while, MDA concentration was higher than control [p<0.05 - p<0.001]. Administration of the extract increased the total thiol and decreased the MDA concentrations [p<0.01 - p<0.001]. It is concluded that the hydro-alcoholic extract of NS possess beneficial effects on learning and memory impairments in repeated seizures model which is accompanied by antioxidant effects in the brain