CONTRACTILE ACTIVITY OF ISOLATED PREPARATIONS OF THE RAT PORTAL VEIN UNDER THE INFLUENCE OF ACETYLCHOLINE AND L-ARGININE

In acute experiments on rats, using the strain gauge method, the effect of acetylcholine and L-arginine on the smooth muscles of isolated preparations of the portal vein (PV) of the rat liver were investigated. Acetylcholine (1х10(-4) M and L-arginine (5.6х10(-4) M caused contraction of PV with intact endothelium. Deendothelization of the preparations by saponin (1 mg/ ml) led to decrease in the amplitude of contraction under the influence of the studied substances. The results obtained indicate an endothelium-dependent contraction of PV under the influence of acetylcholine and L-arginine, as well as the probable involvement of nitric oxide transformation products of endothelial origin in inducing such reaction.