Cerebrovascular permeability in acute hypertension: effect of flunarizine.
The pattern of Evans blue extravasation in the brain in norepinephrine-induced acute hypertension is similar to our previous observations using horseradish peroxidase as a tracer. Pretreatment with flunarizine IV resulted in significant reduction of RISA leakage in all regions of the brains of acutely hypertensive rats. The reduction in RISA leakage in the drug-treated hypertensive group is not attributable to differences in the blood pressure elevations which were not significantly different in both groups. These studies suggest a role for calcium in the increased endothelial permeability occurring in cerebral vessels in acute hypertension. Further morphological studies are required to determine whether flunarizine reduces permeability by decreasing pinocytosis.
Nag
S
S
Department of Pathology (Neuropathology), Queen's University, Kingston, Ontario, Canada.
Young
L
L
D000208:Acute Disease; D000818:Animals; D002199:Capillary Permeability / Q000187:drug effects; D002560:Cerebrovascular Circulation / Q000187:drug effects*; D005070:Evans Blue; D005444:Flunarizine / Q000494:pharmacology*; D006973:Hypertension / Q000378:metabolism / Q000503:physiopathology*; D007457:Iodine Radioisotopes; D051381:Rats; D011920:Rats, Inbred WF; D012709:Serum Albumin / Q000378:metabolism; D012711:Serum Albumin, Radio-Iodinated
D007457:Iodine Radioisotopes; D012709:Serum Albumin; D012711:Serum Albumin, Radio-Iodinated; D005070:Evans Blue; D005444:Flunarizine