Differential effects of short- and long-term bupivacaine treatment on α1-adrenoceptor-mediated contraction of isolated rat aorta rings and the reversal effect of lipid emulsion  

作　　者：Hao GUO He-feiZHANG Wen-qi XU Qian DU Jing ZHAO Lei-ming REN 

机构地区：[1]Institute of Chinese Integrative Medicine, Hebei Medical University, Shijiazhuang 050017, China

出　　处：《Acta Pharmacologica Sinica》2015年第8期976-986,共11页中国药理学报（英文版）

摘　　要：Aim： Arterial function is significantly influenced by bupivacaine at both clinically relevant concentrations and toxic concentrations, but the underlying mechanisms are not fully understood. In the present study we investigated the role of al-adrenoceptors in bupivacaine effects on isolated rat aortas. Methods： Isolated aortic rings were prepared from rats and suspended and acetylcholine （ACh）-induced vasodilation were recorded through an system. n an organ bath. Phenylephrine （Phe）-induced vasoconstriction isometric force transducer connected to a data acquisition Results： Administration of bupivacaine （30-300 pmol/L） produced mild vasoconstriction, and this response declined with repeated administrations. Treatment of the aortic rings with bupivacaine （3-30 pmol/L） for 20 min enhanced Phe-induced vasoconstriction, while treatment for 40 rain suppressed Phe-induced vasoconstriction. Both the short- and long-term bupivacaine treatment suppressed ACh-induced vasodilation. Incubation of the aortic rings with 0.2%-0.6% lipid emulsion （LE） for 100 min significantly increased the pD2and Emax values of Phe-induced vasoconstriction, and incubation with 0.4% LE for 100 min reversed the inhibition of bupivacaine on vasoconstriction induced by Phe （30 μmol/L）. In contrast, incubation with LE suppressed ACh-induced vasodilation, even at a lower concentration and with a 5-min incubation. Conclusion： Bupivacaine exerts dual effects on α1-adrenoceptor-mediated vasoconstriction of isolated rat aortic rings： short-term treatment enhances the response, while long-term treatment inhibits it; the inhibition may be reversed via long-term incubation with LE.Aim： Arterial function is significantly influenced by bupivacaine at both clinically relevant concentrations and toxic concentrations, but the underlying mechanisms are not fully understood. In the present study we investigated the role of al-adrenoceptors in bupivacaine effects on isolated rat aortas. Methods： Isolated aortic rings were prepared from rats and suspended and acetylcholine （ACh）-induced vasodilation were recorded through an system. n an organ bath. Phenylephrine （Phe）-induced vasoconstriction isometric force transducer connected to a data acquisition Results： Administration of bupivacaine （30-300 pmol/L） produced mild vasoconstriction, and this response declined with repeated administrations. Treatment of the aortic rings with bupivacaine （3-30 pmol/L） for 20 min enhanced Phe-induced vasoconstriction, while treatment for 40 rain suppressed Phe-induced vasoconstriction. Both the short- and long-term bupivacaine treatment suppressed ACh-induced vasodilation. Incubation of the aortic rings with 0.2%-0.6% lipid emulsion （LE） for 100 min significantly increased the pD2and Emax values of Phe-induced vasoconstriction, and incubation with 0.4% LE for 100 min reversed the inhibition of bupivacaine on vasoconstriction induced by Phe （30 μmol/L）. In contrast, incubation with LE suppressed ACh-induced vasodilation, even at a lower concentration and with a 5-min incubation. Conclusion： Bupivacaine exerts dual effects on α1-adrenoceptor-mediated vasoconstriction of isolated rat aortic rings： short-term treatment enhances the response, while long-term treatment inhibits it; the inhibition may be reversed via long-term incubation with LE.

关 键 词：BUPIVACAINE aortic rings α1-adrenoceptors PHENYLEPHRINE VASOCONSTRICTION ACETYLCHOLINE VASODILATION lipids emulsions local anesthetics 

分 类 号：Q463[生物学—生理学] TS201.22[轻工技术与工程—食品科学]