The involvement of neuropeptide Y Y1 receptors in the blood pressure baroreflex: studies with BIBP 3226 and BIBO 3304.
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 microg/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 microg/kg) reduced the pressor response elicited by the carotid occlusion to 12 +/- 4 mmHg. The simultaneous administration of BIBP 3226 plus prazosin rose the systemic blood pressure following the occlusion only 9 +/- 2 mmHg, supporting the involvement of neuropeptide Y in vascular sympathetic reflexes.
Capurro
D
D
Department of Physiology, Faculty of Biological Sciences, P. Catholic University of Chile, Santiago.
Huidobro-Toro
J P
JP
D000818:Animals; D001120:Arginine / Q000031:analogs & derivatives* / Q000494:pharmacology; D017704:Baroreflex / Q000187:drug effects* / Q000502:physiology; D001794:Blood Pressure / Q000187:drug effects* / Q000502:physiology; D002317:Cardiovascular Agents / Q000494:pharmacology*; D002339:Carotid Arteries / Q000187:drug effects; D002415:Cats; D004305:Dose-Response Relationship, Drug; D008026:Ligation; D009478:Neuropeptide Y / Q000494:pharmacology*; D017476:Receptors, Neuropeptide Y / Q000037:antagonists & inhibitors* / Q000502:physiology
C092926:BIBP 3226; D002317:Cardiovascular Agents; D009478:Neuropeptide Y; D017476:Receptors, Neuropeptide Y; C097212:neuropeptide Y-Y1 receptor; D001120:Arginine; C117416:BIBO 3304