title: Acute systemic and regional hemodynamic effects of alpha 1-adrenoceptor blockade in conscious spontaneously hypertensive rats.
abstract: The acute hemodynamic effect of the selective alpha1-antagonist, 2-[4-(n-butyryl)-homopiperazine-1-y1]-4-amino-6,7-dimethoxy-quinazoline (bunazosin; E-643), was studied by the microsphere technique in 62 conscious spontaneously hypertensive rats. We found that a large fall in total peripheral resistance with a moderate increase in cardiac output accounted for the moderate decrease in arterial pressure; the heart rate did not change; the skeletal muscle, brain, heart, and gastrointestinal tract sensitively dilated, and kidney less sensitively dilated, their resistance vessels, with little change in their blood flow.
mesh_terms: D000317:Adrenergic alpha-Antagonists / Q000494:pharmacology*; D000818:Animals; D003243:Consciousness; D004305:Dose-Response Relationship, Drug; D006439:Hemodynamics / Q000187:drug effects*; D006973:Hypertension / Q000503:physiopathology*; D008297:Male; D011799:Quinazolines / Q000008:administration & dosage / Q000494:pharmacology*; D051381:Rats; D011918:Rats, Inbred SHR / Q000502:physiology; D012039:Regional Blood Flow / Q000187:drug effects
chemical_list: D000317:Adrenergic alpha-Antagonists; D011799:Quinazolines; C018176:bunazosin