EFFECTS OF NILVADIPINE ON NEURONAL FUNCTION IN THE ISCHEMIC CAT BRAIN

The effect of nilvadipine, a dihydropyridine-type calcium entry blocker, on neuronal function during and following ischemia was investigated with a model of focal cerebral ischemia in cats and was compared with that of nicardipine. Drugs were given intravenously 30 minutes before occlusion of the left middle cerebral artery (MCA). Occlusion of the left MCA for 60 minutes was followed by reperfusion for 90 minutes. The amplitude of the somatosensory evoked potentials (SEPs), and the residual relative regional cortical blood flow in the left ectosylvian gyrus and the left posterior sigmoid gyrus, were higher or had a tendency toward higher values in the nilvadipine-treated (32-mu-g/kg) group than in other groups. After reperfusion, the amplitude of SEPs rapidly recovered in the nilvadipine-treated groups. When administered before MCA occlusion, nilvadipine improved neuronal function measured by SEPs both during and following the ischemic period. Thus, nilvadipine is effective against neuronal dysfunction in focal cerebral ischemia.