The involvement of neuropeptide Y Y1 receptors in the blood pressure baroreflex: studies with BIBP 3226 and BIBO 3304

Abstract

To ascertain the role of the neuropeptide Y Y1 receptors in the vascular manifestations of the sympathetic baroreflex, 10-s bilateral carotid occlusions were performed in anesthetized cats; systemic blood pressure was monitored continually. This maneuver rose systolic blood pressure in 23±2 mmHg. Following 100 μg/kg BIBP 3226 or BIBO 3304 i.v., the increase in blood pressure elicited by the occlusions was only 14±1 and 15 mmHg, respectively. Both BIBP 3226 and BIBO 3304 displaced significantly 5.5 fold rightward the pressor dose-response curve elicited by exogenous neuropeptide Y, without altering the norepinephrine curve. Prazosin (10 μg/kg) reduced the pressor response elicited by the caro..