[Effect of nitric oxide on the myoelectric activity of sphincter of Oddi and arterial blood pressure of rabbit].
Thirty-two rabbits were used to investigate the effect of nitric oxide (NO) on the myoelectric activity of the sphincter of Oddi (SO) and arterial blood pressure. Intravenous infusion of NG-nitro-L-arginine (L-NNA), an inhibitor of nitric oxide synthase (NOS), caused increase in SO phasic wave amplitude and arterial blood pressure. The increase in SO phasic wave amplitude by infusion of L-NNA was reversed by L-arginine, but arterial blood pressure remained at a high level. It was observed that SO phasic wave amplitude, frequency and arterial blood pressure were significantly decreased by intravenously infusion of sodium nitroprusside (SNP), a substance producing NO. These observations suggest that (1) NO inhibits the resting activity of SO and modulates relaxation of vascular smooth muscle; (2) different tissues show different responses to L-NNA and L-arginine.
Zhang
M
M
Department of Pathophysiology and Outpatient Department, Hebei Medical University, Shijiazhuang 050017.
Ding
C H
CH
Zhang
L W
LW
Yang
S Y
SY
D000818:Animals; D001794:Blood Pressure / Q000187:drug effects*; D004576:Electromyography; D004594:Electrophysiology; D008297:Male; D009130:Muscle, Smooth / Q000502:physiology; D009569:Nitric Oxide / Q000502:physiology*; D019335:Nitroarginine / Q000494:pharmacology; D009599:Nitroprusside / Q000494:pharmacology; D011817:Rabbits; D009803:Sphincter of Oddi / Q000502:physiology*
D009599:Nitroprusside; D019335:Nitroarginine; D009569:Nitric Oxide