解毒健脾中药提取物对镉中毒的预防作用

Preventive Effect of Extract of an Traditional Chinese Medicine on the Cadmium Toxicity

采用ＳＤ 大鼠离体气管，与重金属解毒药二巯基丁二酸（ ＤＭＳＡ） 对照，观察了解毒健脾中药提取物０２ 号（ 中药０２ 号） 对呼吸道平滑肌镉染毒的保护作用。结果显示：（１） 镉对气管平滑肌的抑制作用在一定范围内呈浓度依赖性。当氯化镉浓度为６ ｍ ｍｏｌ／Ｌ，９ ｍ ｍ ｏｌ／Ｌ 时，气管平滑肌对乙酰胆碱的最大收缩效应（Ｅｍａｘ） 从９８ ±３（ ｎ ＝ ６） 分别降至５３ ±２８（ ｎ ＝ ７ ，Ｐ＜ ０－０５） 、１９ ±１５（ ｎ ＝ ７ ，Ｐ＜ ０－００１ ；（２） 当用中药０２ 号预处理气管后，氯化镉的抑制作用减弱，Ｅｍａｘ 从１９ ±１５ 恢复至６２ ±２７（ ｎ ＝ ５ ，Ｐ＜ ０－０５） 和５６ ±２８（ ｎ ＝ ５ ，Ｐ＜ ０－０５） 与用ＤＭＳＡ 后（Ｅｍ ａｘ 恢复至４０ ±１０ 和７０ ±１０） 比较，两者间无显著性差异（ Ｐ＞ ０－０５） 。氯化镉对气管平滑肌收缩的抑制作用，可能与其影响乙酰胆碱对Ｍ 受体的亲和力和（ 或） 抑制钙通道有关；中药０２ 号的作用，可能与ＤＭＳＡ 的解毒机理相同，即与氯化镉形成络合物，而发挥预防作用。

Compared with acid dimercaptosuccinate(DMSA),the preventive effect of extract extracted from a Chinese formula“N 02 Detoxifying and Spleen strengthening”(N 02),was studied on the isolated SD rat tracheal smooth muscle pretreated with cadmium chloride(CdCl 2).The data showed that:(1)Cd dose dependently inhibited the contracted effect of rat tracheal smooth muscle in certain range of concentrations.At the concentrations of 6 mmol/L and 9 mmol/L of Cd,the maximal effect(Emax) of strips to acetylcholine(ACh) significantly decreased from 98±3( n=6) to 53±28( n=7,P<0 05) and 19±15( n=7,P<0 001) ,respectively;(2)After pretreatment with N 02,the inhibition of Cd to the contracted isolated strips was significantly reduced and the Emax was reestablished to 62±27( n=5,P<0.05 ) and 56±28( n=5,P<0 05) ,respectively,which showed no significant difference with that of DMSA(40±10 and 70±10, P>0 05) ,The inhibition effect of Cd on the contracted airway smooth muscle would be concerned in Cd's influence on affinity of muscarinic receptors to ACh and(or) in its inhibition on the calcium channel.The mechanism of preventive effect of N 02 was probably similar to that of DMSA,forming the chelate with Cd.It indicated that traditional chinese medicine might be a new way to prevent or treat cadmium poisoning.