Central administration of a nitric oxide synthase inhibitor causes pressor responses via the sympathetic nervous system and the renin-angiotensin system in Wistar rats

• Published in: Neuroscience letters 1998-04, Vol.245 (2), p.109-112
• Main Authors: Moriguchi, Shigeki, Ohzuru, Noriyasu, Koga, Nobuhiro, Honda, Kenji, Saito, Ryo, Takano, Yukio, Kamiya, Hiro-o
• Format: Article
• Language: English
• Subjects: Angiotensin II AT1 receptor; Animals; Biological and medical sciences; Blood Pressure - drug effects; Central cardiovascular regulation; Fundamental and applied biological sciences. Psychology; Heart Rate - drug effects; Injections, Intraventricular; Male; Motor control and motor pathways. Reflexes. Control centers of vegetative functions. Vestibular system and equilibration; NG-Nitroarginine Methyl Ester - administration & dosage; Nitric oxide; Nitric Oxide Synthase - antagonists & inhibitors; Nitric oxide synthase inhibitor; Nitric Oxide Synthase Type I; Pentolinium Tartrate - administration & dosage; Rats; Rats, Wistar; Renin-Angiotensin System - drug effects; Renin-Angiotensin System - physiology; sympathetic nervous system; Sympathetic Nervous System - drug effects; Sympathetic Nervous System - enzymology; Sympathetic Nervous System - physiology; Vertebrates: nervous system and sense organs
• ISSN: 0304-3940; 1872-7972
• DOI: 10.1016/S0304-3940(98)00182-7

The central roles of nitric oxide (NO) in regulations of the blood pressure and heart rate were examined in anesthetized rats. Intracerebroventricular (i.c.v.) injection of N ω -nitro- l-arginine methyl ester ( l-NAME) caused dose-dependent increase in the blood pressure and heart rate. The pressor response of the blood pressure to l-NAME (2 μmol, i.c.v.) was reduced by l-arginine (5 μmol, i.c.v). Pretreatment with a ganglionic blocker, pentolinium (10 mg/kg, i.v.), significantly inhibited both pressor responses induced by l-NAME (2 μmol, i.c.v). The later pressor response of the blood pressure to l-NAME was also inhibited by the angiotensin II AT-1 blocker losartan (10 mg/kg, i.v). These results suggest that the response of the blood pressure to l-NAME is mediated by both the sympathetic nervous system and the renin-angiotensin system.