RESUMO
AIM: To assess the effects of propofol and sevoflurane on the contraction elicited by dopamine, adrenaline and noradrenaline on isolated human umbilical arteries. METHODS: Umbilical arteries were cut into endothelium-denuded spiral strips and suspended in organ baths containing Krebs-Henseleit solution bubbled with O2 +CO2 mixture. Control contraction to phenylephrine (10(-5) M) was recorded. Response curves were obtained to 10(-5) M dopamine, 10(-5) M adrenaline or 10(-5) M noradrenaline. Afterwards, either cumulative propofol (10(-6) M, 10(-5) M and 10(-4) M) or cumulative sevoflurane (1.2%, 2.4% and 3.6%) was added to the organ bath, and the responses were recorded. Responses are expressed percentage of phenylephrine-induced contraction (mean ± standard deviation) (P < 0.05 = significance). RESULTS: Propofol and sevoflurane elicited concentration-dependent relaxations in strips pre-contracted with dopamine, adrenaline and noradrenaline (P < 0.05). Highest (10(-4) M) concentration of propofol caused significantly higher relaxation compared with the highest (3.6%) concentration of sevoflurane in the contraction elicited by dopamine. High (10(-5) M) and highest concentrations of propofol caused significantly higher relaxation compared with the high (2.4%) and highest concentrations of sevoflurane on the contraction elicited by adrenaline. High and highest concentrations of sevoflurane caused significantly higher relaxation compared with the high and highest concentrations of propofol on the contraction elicited by noradrenaline. CONCLUSION: Dopamine, adrenaline and noradrenaline elicit contractions in human umbilical arteries, and noradrenaline causes the highest contraction. Both propofol and sevoflurane inhibit these contractions in a dose-dependent manner. Propofol caused greater relaxation in the contractions elicited by dopamine and adrenaline while sevoflurane caused greater relaxation in the contraction elicited by noradrenaline.