Abstract: AIM: To study the protective effect of Nimodipine on porcine basilar artery oxidative stress injury induced by hydrogen peroxide (H₂O₂ ). METHODS: Porcine basilar artery rings without endothelium were isolated and allocated in 6 groups:control, H₂O₂ (2×10^-4 mol/L) injury, Vitamin C (10^-4 mol/L) pretreatment, Nimodipine with high, moderate and low dose pretreatment (5×10^-6, 5×10^-7, 5×10^-8mol/L), which were handled with organ chamber technique.The tensive changes after they were treated by vaso-excitor material KCl, phenylephrine and H₂O₂ were compared and the activity changes of superoxide dismutase (SOD), malondialdehyde (MDA), catalase (CAT) and glutathione peroxidase (GSH-PX) were detected. RESULTS: (1) Compared with those in the control group, the vascular ring of the H₂O₂ injury group showed more significant contractile response to KCl and phenylephrine.Nimodipine with high, moderate and low doses pretreatment inhibitted the contractile response of the vascular ring to KCl and phenylephrine in dose dependent.(2) Compared with those in the control group, the content of MDA in H₂O₂ injury group was increased, and the activities of SOD, CAT, GSH-PX were degraded.They all have significant difference (P<0.05).Compared with the control group, Nimodipine with high, moderate and low doses pretreatment all degraded the content of MDA, and increased the activity of SOD, CAT, GSH-PX.They all had significant difference (P<0.05). CONCLUSION: Nimodipine can inhibit the contraction of vascular and prevent brain arteria basilaris from injuring.

Key words: Nimodipine, hydrogen peroxide, basilar artery, oxygen free radical, vascular smooth muscle cell