Propofol and thiopental attenuate the contractile response to vasoconstrictors in human and porcine coronary artery segments

Abstract

The effects of propofol and thiopental on three vasoconstrictors, acetylcholine, histamine, and serotonin were studied in isolated porcine and human coronary artery rings. Propofol and thiopental attenuated the contractile response to all mediators in a dose-dependent manner. This dilating effect was fairly weak using low concentrations (propofol 1 microg mL-1 and 10 microg mL-1, thiopental 5 microg mL-1 and 10 microg mL-1). In the presence of high concentrations (propofol 100 microg mL-1, thiopental 50 microg mL-1) marked relaxation was observed (propofol -32% up to -49%, P < 0,05; thiopental -23% up to -67%, P < 0.05). These dilating effects were seen both in intact and denuded rings, the differences were not significant. Human coronary artery segments were relaxed by thiopental (-22% to -76%) and propofol (-11% to -67%) to a similar extent. Our data indicate that propofol and thiopental relax isolated coronary segments in a dose-dependent manner, and that there is no evidence that these effects are dependent of endothelial factors.

Amplification by Hyperoxia of Coronary Vasodilation Induced by Propofol

“…For Yamanoue et al (4), this vasodilation is non-endothelium-dependent on porcine coronary arteries and involves antagonism of calcium channels. These results are consistent with those reported in canine and human coronary arteries (6,11). By contrast, in rat coronary arteries, propofol induces a significant endothelium-dependent vasodilation that is not mediated by opening of the K ATP channels (3).…”

“…Although numerous in vitro studies reported a coronary vasodilation, previous results remain a subject of controversy. In human coronary vessels, propofol induced a dose-dependent vasodilation (11). These results have been confirmed in numerous animal species (4,8,9).…”

“…In canine coronary arteries, propofol induces a biphasic change resulting in a vasodilation only at therapeutic (6) or at supratherapeutic (5,10) concentrations. However, some authors reported a dose-dependent vasodilator effect of propofol in several species, including human coronary arteries (4,9,11). In addition, the mechanism of propofol coronary vasodilation is a subject of controversy.…”

Bradycardia during critical care intubation: mechanisms, significance and atropine: Figure 1

“…Even if induction drugs do not provoke bradycardia, they can have important effects on the circulation by inducing vasodilatation as is the case for propofol,58 59 thiopental58 60 and for the opiates morphine,61 sufentanyl62 and remifentanil 63…”

Propofol Attenuates Ovalbumin-Induced Smooth Muscle Contraction of the Sensitized Rat Trachea: Inhibition of Serotonergic and Cholinergic Signaling

“…In the present study, IgE-related OA-induced tracheal smooth muscle contraction was significantly attenuated by propofol. Klockgether-Radke et al (18) reported that propofol attenuates 5-HT-induced contraction of isolated coronary segments of human and porcine coronary The values for tension were expressed as the changes from baseline tension in a 5-HT and ACh concentration-response curve. The values for tension were expressed as the changes from the tension just before each stimulation was performed in EFS frequencyresponse curve.…”