Impromidine-induced changes in the permeability of the blood-brain barrier of normotensive and spontaneously hypertensive rats
Boertje, S.B.; Le Beau, D.; Ward, S.
Research Communications in Chemical Pathology and Pharmacology 69(2): 249-252
1990
ISSN/ISBN: 0034-5164 PMID: 1975703 Document Number: 360239
Previous studies suggested histamine receptors mediate changes in the cerebrovascular permeability of rats. To test this, we investigated the effects of impromidine, a specific agonist at the histamine H2-receptor, on blood pressure and permeability of the blood-brain barrier (BBB). Impromidine produced dose-dependent hypotension in Wistar-Kyoto (WKY) and spontaneously hypertensive (SHR) rats. Two higher doses of impromidine increased BBB permeability to 99mTc-sodium pertechnetate in WKY rats; however, two lower doses decreased permeability in SHR rats. All doses of impromidine increased cerebrovascular permeability to 131I-labeled serum albumin in both species. Doses of the drug were 100 times greater than those required to produce similar alterations using histamine.