[The effect of calcium antagonists nimodipin, verapamil, diltiazem and flunarizin on local cerebral blood flow in rabbits in chronic experiments].

The influence of calcium antagonists nimodipin (0.03 and 0.06 mg/kg), verapamil (0.3 and 0.6 mg/kg), diltiazem (0.3 and 0.6 mg/kg), flunarizin (0.3 and 0.6 mg/kg), administered by the ear vena, was studied on the local cerebral blood flow of the cortex of 9 rabbits by means of the method of hydrogen clearance with inhalation of hydrogen under the conditions of chronic experiments. Platinum microelectrodes with diameter of 100 microns and length of 2 mm were implanted in the frontal and sensomotor regions of the cerebral cortex a month before the onset of the experiments. Calcium antagonists nimodipin, verapamil, diltiazem and flunarizine increased the local blood flow in the cerebral cortex of rabbits under the conditions of chronic experiments. The effect of nimodipin and verapamil on the local blood flow of cerebral cortex was more manifested in comparison with the effect of flunarizin and diltiazem. Nimodipin and verapamil, on the one side, and flunarizin and diltiazem, on the other, had almost equal effect, which elevated the local blood flow in the cerebral cortex of rabbits under conditions of chronic experiments.