Vasoconstrictive effects of human post-hemorrhagic cerebrospinal fluid on cat pial arterioles in situ

Abstract

Cat cortical arterioles were exposed in vivo to CSF from 4 patients with subarachnoid hemorrhage due to a ruptured intracranial aneurysm. Pial arteriolar caliber was measured by the television image-splitting technique. There was a consistent vasoconstrictive response to CSF. This effect could be ascribed neither to the pH of the CSF nor to the K concentration. The vasoconstriction, which was more pronounced with decreasing arteriolar caliber, could be resolved by the perivascular application of nifedipine.