Direct vasodilator effect of propofol on isolated rabbit vessels [PROPOFOLUN IZOLE TAVSAN DAMARLARINDA DIREKT VAZODILATOR ETKISI]

It has been demonstrated that propofol produces hypotension partially by its direct endothelium-independent vasodilatory effect on vascular smooth muscle. The present study was performed to investigate the role of local autocoid mediators on the direct vasodilator effect of propofol on isolated rabbit vessels. It was observed that propofol decreased basal tone of coronary vessels in Langendorff isolated rabbit heart, concentration, dependently and induced a concentration-dependent relaxation in the endothelium-denuded, isolated rabbit thoracic aorta precontracted with 5-hydroxytryptamine (5-HT), histamine, phenylephrine, PGF2? or KCl. But the difference between the concentrations inducing 50% relaxation was found to be statistically insignificant (p>0.05). Some aortic rings were contracted with 5-HT, histamine, phenylephrine and PGF2? and concentration-response curves were obtained. It was observed that when propofol was added prior to contractile agent, only the curve for 5-HT was shifted to right with a significant decrease in the maximum response. It was concluded that vasodilation induced by propofol might be mediated by a decrease in intracellular Ca++ effect and possibly, the blocking effect of propofol on the 5-HT receptors of vascular smooth muscle might play an additional role in this vasodilation.