[Cerebral blood flow function during altered cholinergic mediation]

The study of cerebral blood flow was performed with the aid of hydrogen clearance technique and the cinema-television method in alteration of cholinergic transmission by means of phosphorus-organic inhibitors of cholinesterase and a cholinolytic agent in unanesthetized rats. The enzyme inhibition by 60-70% sharply increased the velocity of blood flow in the microvessels of cerebral cortex and in the sagittal sinus. A considerable vasodilation of pial vessels occurred. Atropine administration reduced the velocity of both the cortical and the total blood flow, increasing the lumen of pial vessels in intact animals. Whereas atropine administration against the background of the inhibitors action normalized the blood low velocity with no elimination of the vasodilation of pial arteries. The findings suggest that atropine widely used in poisoning with various inhibitors of cholinesterase, does not normalize the tonus of cerebral vessels.