Effects of nimodipine on EEG and 31P-NMR spectra during and after incomplete forebrain ischemia in the rat.
The effect of nimodipine was studied on EEG power density spectra as well as on 31P-NMR spectra of the brain before, during and after four-vessel occlusion (FVO) in the restrained conscious rat. EEG-spectral analysis: eight rats were submitted to 5 min FVO and four of them received nimodipine (1 mg/kg orally) 75 min before FVO. In the nimodipine-treated rats the post-ischemic overshoot of the EEG power density was significantly lower for the theta, alpha and beta band activity. 31P-NMR spectroscopy: the relative concentrations of phosphocreatine (PCr), ATP and Pi as well as intracellular pH were measured at different intervals after 10 min FVO (n = 10). All values normalised within 15-30 min after restoration of cerebral blood flow without significant differences between nimodipine-treated and control rats. It is concluded that pretreatment with nimodipine has a decreasing effect on the overshoot in EEG power density after transient incomplete forebrain ischemia. This effect was not correlated to significant changes in cerebral 'energy state', as measured by 31P-NMR spectroscopy.
D000818:Animals; D002545:Brain Ischemia / Q000503:physiopathology*; D004569:Electroencephalography; D009682:Magnetic Resonance Spectroscopy; D008297:Male; D009539:Nicotinic Acids / Q000494:pharmacology*; D009553:Nimodipine; D051381:Rats; D011919:Rats, Inbred Strains; D013997:Time Factors
D009539:Nicotinic Acids; D009553:Nimodipine