Baroreceptor reflexes and vascular reactivity during inhibition of nitric oxide synthesis in conscious rabbits.

摘要: The effect of the nitric oxide (NO) synthase inhibitor N-nitro-L-arginine (NOLA) on vascular reactivity and baroreceptor heart rate reflex was examined in chronically instrumented conscious rabbits. NOLA (15 mg/kg i.v.) significantly increased mean arterial pressure hindlimb resistance decreased rate. Increases decreases were produced by intravenous injection phenylephrine sodium nitroprusside respectively values obtained relating blood to fitted a sigmoid curve. reduced lower plateau pressure--heart curve but did not affect sensitivity. Depressor vasodilator responses acetylcholine impaired whereas enhanced. pressor vasoconstrictor enhanced presence NOLA. We conclude that bradycardia does result from change continuous generation NO appears be important regulating basal modulating both agents.