Effect of nilvadipine on memory impairment and hippocampal malondialdehyde in rats with 4-vessel occlusion ischemia

Abstract

Purpose: Nilvadipine is a dihydropyridine-type calcium channel blocker with emanating neuroprotective properties in various models of neuronal diseases. This study aimed at investigating the prophylactic effect of nilvadipine on memory impairment and hippocampal malodialdehyde (MDA) levels in global brain ischemia model induced by 4-vessel occlusion ischemia (4-VO) in rat. Materials and methods: The 4-VO ischemia was induced in Wistar rats by occluding the vertebral arteries permanently by cauterization. The common carotid arteries were twice occluded bilaterally for 10 minute at 60 minute interval. One week after 4-VO the memory was evaluated measuring the correct and error choices in 8-armed radial maze. The ischemiareperfusion- induced damage was evaluated measuring level of MDA in the hippocampus using thiobarbituric acid method. The study involved three groups: sham, ischemia-control and ischemia nilvadipin. Nilvadipine (3.2 mg/kg/day) was administerd for 7 days prior to 4-VO Results: The 4-VO impaired memory performance by decreasing the correct choices (long termreference memory) and increasing the error choices (short term-working memory) (p<0,001). Nilvadipine improved the performance by increasing the correct choices (p<0.002) and decreasing the error choices (p<0.05). Nilvadipine decreased (p<0.001) the elevated MDA induced by 4-VO. Conclusion: The prophylactic treatment with nilvadipine improved memory impairment and reduced the elevated hippocampal MDA induced by 4-VO. The prophylactic use of nilvadipine could be beneficial for inhibiting the ischemia related memory impairment in risky patients.