【作者】 杨振华； 冯燕； 张月霞； 张全喜； 孟紫强； 董川；

【Author】 YANG Zhenhua;FEN Yan;ZHANG Yuexia;ZHANG Quanxi;MENG Ziqiang;DONG Chuan;Institute of Environmental Science, Shanxi University;

【机构】 山西大学环境科学研究所；

【摘要】 <正>焦亚硫酸钠(SMB)作为一种常见的食品添加剂,在食品行业应用广泛。本文研究了SMB对去甲肾上腺素(NE)预激的离体大鼠血管环的舒张效应,同时对其可能涉及的K离子通道舒张机制进行了研究。结果表明:(1)SMB可以浓度依赖性的舒张NE预激的大鼠血管环(未去内皮,EC50为830±97μmol·L-1;去内皮,EC50为1087±139μmol·L-1)。(2)在低浓度下SMB诱导的舒张效应是内皮依赖性的,且其最大舒张率约为20%,然而高浓度下SMB诱导的舒张效应与内皮无关,且其舒张率可达90%以上。(3)四乙基氯化铵(TEA,非特异性钾离子通道阻断更多还原

【Abstract】 Sodium metabisulfite（SMB） is most commonly used as a food additives. In the present paper, the vasodilator effects of SMB and roles of K+ channels on isolated rat aortic rings were studied. The results show that:（1） SMB could relax isolated aortic rings precontracted by norepinephrine in a concentration-dependent manner for both endothelium-intact(EC50, 830 ± 97 μmol·L^-1) and endothelium-denuded aortic rings(EC50, 1087 ± 139 μmol·L^-1).（2）The maximal endotheliumdependent vasorelaxation was approximately 20% whereas that not depending on the presence of the endothelium was more than 90%.（3） The SMB induced vasorelaxation was partically inhibited by tetraethylammonium（TEA, the inhibitor of non-specific K+ channel）.（4） The vasorelaxation of 1000 μM SMB was partially inhibited by glibenclamide（the inhibitor of ATP-sensitive K+（KATP）channel）.（5） The vasorelaxant effects induced by 50 or 200 μmol·L^-1 SMB were partially inhibited by iberiotoxin(Ib Tx, the inhibitor of big-conductance Ca2+-activated K+ channel（BKCa）. These results led to the conclusions that the vasorelaxation of SMB at low concentrations(<400 μmol·L^-1) was endothelium-dependent and mediated by BKCa channel, but at high concentrations(>500 μmol·L^-1) was endothelium-independent and mediated by KATP channel.更多还原