[The influence of 2-ethyl-3-(4-hydroxy-benzoyl)- benzofuran on the contraction of pial arterial muscles (author's transl)].

By means of perivascular perfusion of thin sections of pial arteries with differently composed cerebrospinal fluid (CSF) the vessel diameters can be influenced. In cats, anesthetized with pentobarbital, addition of serotonin, norepinephrine or calcium to an artificial CSF which was infused through micropipettes into the perivascular space of the pial arteries, caused constrictions of the arteries contacting the modified CSF. Hyperventilation or perivascular perfusion of alkaline CSF also caused reduction of the pial arterial diameters. 2-Ethyl-3-(-hydroxy-benzoyl)-benzofuran (benzarone) inhibited or abolished the constrictions elicited by the above mentioned stimuli. The effect was dose-dependent. High doses of benzarone caused pial arterial dilations: The inhibition of the calcium induced constriction especially, seems worth mentioning since this ion plays a central role in the contraction mechanisms of the vascular smooth muscle cells.