This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Request Permissions Citing Articles Citing Articles via Google Scholar Google Scholar Articles by Dieguez, G. Articles by Lluch, S. Search for Related Content PubMed PubMed Citation Articles by Dieguez, G. Articles by Lluch, S.

Stroke, Vol 11, 372-376, Copyright © 1980 by American Heart Association

ARTICLES

Analysis of cerebrovascular action of diazoxide in conscious goats

G Dieguez, B Gomez and S Lluch

The effects of diazoxide on cerebral blood flow were evaluated in unanesthetized goats under control conditions and after selective blockade of adrenergic or cholinergic receptors in cerebral vessels. Injections of diazoxide (1-27 mg) into the internal maxillary artery produced dose-dependent increases in cerebral blood flow, an increase of 90% occurring with the highest dose. Administration of phentolamine, propranolol, or atropine into the internal maxillary artery did not modify the cerebrovascular response to diazoxide. In reserpine-treated animals the cerebral effects of diazoxide were also unchanged. Intravenous injections of diazoxide (150-400 mg) produced sustained hypotension and tachycardia whereas cerebral blood flow was maintained within normal values or increased slightly. The normal cerebral vasoconstriction obtained with injections of norepinephrine directly into the internal maxillary artery was unaffected during the diazoxide induced-hypotension. These findings show that diazoxide exerts a powerful vasodilatory effect on cerebral vessels through mechanisms other than blockade of alpha-adrenergic receptors or inhibition of adrenergic activity. The results also indicate that activation of beta- adrenergic or atropine-sensitive vascular receptors in the cerebral response to diazoxide is negligible.