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目的：观察镉对离体家兔空肠力学特性的影响。方法：取大耳白兔２０只，各制３个离体空肠平滑肌条标本，共６０个，随机分成５组，分别以盐水和４个剂量氯化镉液对肌条作循环灌注，用张力感受器测量离体空肠平滑的主动张力（ＰＴ）、基础张力（ＲＴ）、主动张力最大收缩速率（ｄＴ／ｄｔｍａｘ）和主动张力最大舒张速率（－ｄＴ／ｄｔｍａｘ）。结果：镉离子１．００８×１０－４ｍｏｌ／Ｌ组见ＰＴ、ｄＴ／ｄｔｍａｘ、－ｄＴ／ｄｔｍａｘ均有不同程度降低，ＲＴ亦有部分降低，随着镉离子浓度增大，观察指标均明显降低，在镉离子２．０１６×１０－４ｍｏｌ／Ｌ组，有８个标本停止主动收缩，随着镉离子浓度增加，停止主动收缩的标本例数随之增加。这些作用可通过换液得到恢复，并且氯化钙可对抗镉的这种作用。结论：镉离子可直接引起空肠肌收缩力降低，早期此作用可被钙离子逆转。
Objective: To observe the effect of cadmium on the jejunum mechanical properties of isolated rabbits. Methods: Twenty rabbits of large white rabbits were divided into three groups. A total of 60 smooth muscle strips of jejunum were randomly divided into 5 groups. The muscle strips were perfused with saline and 4 doses of cadmium chloride solution respectively. Receptors measured ex vivo smooth jejunal active tension (PT), basal tension (RT), active tension maximal contraction rate (dT / dtmax) and active tension maximal diastolic rate (-dT / dtmax). Results: The levels of PT, dT / dtmax and -dT / dtmax were all decreased to some extent in the group of 1.008 × 10-4mol / L cadmium ions, and partly decreased in the RT group. As the concentration of cadmium ion increased, the observation indexes decreased significantly , In the group of 2.016 × 10-4mol / L of cadmium ions, 8 specimens stopped active contraction. With the increase of cadmium ion concentration, the number of specimens with active contraction stopped increasing. These effects are restored by fluid exchange and calcium chloride counteracts this effect of cadmium. CONCLUSION: Cadmium ions can directly reduce the contractility of jejunum, which can be reversed by calcium ion in early stage.