甲醛对大鼠主动脉血管环张力的影响

发布时间：2018-02-26 01:29

  本文关键词： 甲醛 毒性 血管环 大鼠 张力　出处：《山西大学》2015年硕士论文　论文类型：学位论文

【摘要】：自工业革命以来,环境污染就不断增加,而当今时代的人们也越来越关注各类环境污染物对自身产生的危害。其中,作为室内污染物典型代表之一的甲醛与人们的生活息息相关,它不仅可以由外界空气进入人体,更是人体的内源性物质。近年来,大量流行病学研究表明甲醛会对神经系统,免疫系统,生殖系统,呼吸系统,心血管系统等产生一定的毒性作用。已有报道表明甲醛可以引起血管内皮及心肌组织损伤,使血管产生舒张,对动脉粥样硬化,心肌梗塞等心血管疾病的发生有一定的诱发作用。研究甲醛对心血管功能的毒性危害及其作用机理,对其与心血管疾病的研究发展有重要意义,但目前为止,甲醛对心血管系统的影响以及作用机理还未见详细报道。为此展开本研究课题,研究甲醛对大鼠胸主动脉血管环张力的影响以及具体机理。1.采取大鼠胸主动脉血管环体外实验,将不同浓度的甲醛溶液作用于血管环,观察甲醛对血管环张力的影响发现：低浓度下(300μ M),甲醛会使血管环产生一定的收缩作用,较高浓度下(500μ M),甲醛使去内皮血管环和内皮完整血管环均产生舒张作用,并且呈剂量依赖性关系,只有当甲醛浓度大于3 mM时,舒张作用不再增大。在低浓度和高浓度下,甲醛对去内皮血管环以及内皮完整血管环的收缩作用和舒张作用差异均显著,所以甲醛对血管环张力的影响作用与内皮有关。低浓度的甲醛对100 mM KCl预收缩的血管环舒张作用不明显,对20 mM KCl预收缩的血管环有明显的舒张作用；高浓度甲醛对100 mM KCl预收缩的血管环舒张作用明显,而对20 mM KCl预收缩的血管环产生收缩作用。这些结果表明,甲醛能对血管环的张力产生影响,低浓度的甲醛对血管环有小的收缩作用,高浓度下使血管产生舒张作用且有剂量效应关系,甲醛引起的血管舒张效应可能与钾离子通道电导有关。2.L-Ca2+通道阻断剂硝苯地平,大电导钙激活钾离子通道(BKCa)阻断剂IbTx,非特异性钾离子通道阻断剂TEA,一氧化氮合成酶抑制剂L-NAME,可溶性鸟苷酸环化酶抑制剂NS-2028对较高浓度甲醛引起的血管环舒张效应有部分抑制作用。说明甲醛引起的血管环舒张作用机理可能与L-Ca2+通道,BKCa通道,NO-cGMP通路等有关。3.用去甲肾上腺素(NE),氯化钙(CaCl2),氯化钾(KCl)以累积加入的方法收缩血管,研究发现较高浓度甲醛能够对NE,CaCl2,KCl引起的血管收缩效应产生抑制作用,结果表明较高浓度甲醛对电压依赖性钙通道(VDc)和受体操纵钙通道(ROC)有抑制作用。本研究表明较低浓度的甲醛能够使主动脉血管环收缩,较高浓度的甲醛能够使血管环舒张,其对血管环的舒张作用机制可能与不同的离子通道有关。
[Abstract]:Since the Industrial Revolution, environmental pollution has been increasing, and people in the present era are increasingly concerned about the harm caused by various kinds of environmental pollutants to themselves. Formaldehyde, one of the typical indoor pollutants, is closely related to people's life. It can not only enter the human body from the outside air, but also the endogenous substance of the human body. In recent years, a large number of epidemiological studies have shown that formaldehyde can affect the nervous system. The immune system, reproductive system, respiratory system, cardiovascular system and so on have some toxic effects. It has been reported that formaldehyde can cause vascular endothelial and myocardial tissue damage, vasodilation, atherosclerosis, The occurrence of cardiovascular diseases such as myocardial infarction has a certain inducement. It is important to study the toxic effects of formaldehyde on cardiovascular function and its mechanism, and to study and develop the relationship between formaldehyde and cardiovascular diseases, but so far, The effect of formaldehyde on the cardiovascular system and its mechanism have not been reported in detail. Therefore, this study was carried out to study the effect of formaldehyde on the tension of thoracic aortic rings in rats and its specific mechanism. 1. The in vitro experiment of rat thoracic aortic rings was carried out. The effect of formaldehyde on the tension of vascular rings was observed by using different concentrations of formaldehyde solution. It was found that at low concentration of 300 渭 m ~ (-1), formaldehyde would produce a certain contraction effect on the vascular rings. At a higher concentration of 500 渭 m ~ (-1), formaldehyde induced the relaxation of both the endothelium-free and intact vascular rings in a dose-dependent manner. Only when the concentration of formaldehyde was more than 3 mm, the diastolic effect did not increase. The contractile and diastolic effects of formaldehyde on the endothelium-free and intact vascular rings were significantly different. Therefore, the effect of formaldehyde on the tension of vascular rings is related to endothelium. Low concentration of formaldehyde has no obvious effect on the relaxation of 100mm KCl precontracted vascular rings, but has obvious relaxation effect on 20mm KCl precontracted vascular rings. High concentration of formaldehyde had obvious effect on relaxation of 100mm KCl precontracted vascular rings, but on 20mm KCl precontracted rings. These results showed that formaldehyde could affect the tension of vascular rings. The vasodilation effect of low concentration formaldehyde on the vascular ring was small, and the vasodilation effect was related to the potassium channel conductance, and the effect of formaldehyde induced vasodilation was probably related to the potassium channel conductance .2.L-Ca2 channel blocker, nifedipine, at high concentration, the vasodilation effect was found to be in a dose-dependent manner. Effects of IbTx, a large conductance calcium activated potassium channel blocker, tea, an inhibitor of nitric oxide synthase, L-NAMEand NS-2028, on the vasodilation induced by higher concentrations of formaldehyde. The mechanism of vasodilation induced by formaldehyde may be related to the NO-cGMP pathway of L-Ca2 + channel, BKCa channel and so on. The vasoconstriction was induced by adding norepinephrine, CaCl _ 2, KCl _ (1). It was found that high concentration of formaldehyde could inhibit the vasoconstriction induced by KCl. The results showed that high concentration of formaldehyde inhibited VDcand receptor-operated calcium channel (ROC). This study showed that lower concentration of formaldehyde could cause contraction of aortic rings, and higher concentration of formaldehyde could induce vasodilation of aortic rings. The mechanism of vasodilation may be related to different ion channels.
【学位授予单位】：山西大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：X51

【参考文献】

中国期刊全文数据库 前1条

1 韩彩轩;浅谈面制品中甲醛次硫酸氢钠的定性与定量[J];中国食品卫生杂志;1999年01期

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