内皮素受体与下肢慢性静脉功能不全的关系研究

The relationship between endotbelin receptors and chronic venous insufficiency of lower extremities

目的探讨内皮素受体在下肢慢性静脉功能不全中的作用。方法取无明显曲张下肢静脉（对照组）和明显曲张下肢静脉（病变组）各10例，每组再分为内皮完整组和去内皮组，用血管张力描记法测定内皮素A／B受体介导的收缩功能；免疫组化法测定内皮素A／B受体在血管组织中的定位分布。结果内皮素-1（ET-1）和sarafotoxin 6c（S6c）能诱导静脉产生浓度依赖性收缩。ET-1引起内皮完整静脉的对照组和病变组的最大收缩（Emax）及1／2最大收缩浓度的负对数（pD2）分别为132．30％±43．42％和6．03±0．35及19．24％±12．94％和6．78±0．46，病变组的Emax和pD2均明显低于对照组（P〈0．05）；S6c引起病变组和对照组的Emax和pD2分别为30．10％±12．90％和6．54±0．36及9．61％±1．32％和6．75±0．29，病变组Emax明显低于对照组（P〈0．05）。去内皮静脉对照组和病变组$6c引起的Emax和pD2分别为146．18％±32．33％和6．50±0．17及32．93％±3．00％和6．69±0．39，病变组Emax低于对照组（P〈0．05）。内皮素A受体主要分布于血管内皮，内皮素B受体主要分布于平滑肌。病变组静脉中内皮素受体位点分布均显著减少。结论下肢慢性静脉功能不全患者曲张下肢静脉内皮素A／B受体分布明显减少，收缩功能明显减弱，表明内皮素A／B受体表达下调和功能减低与下肢慢性静脉功能不全病变相关。

Objective To investigate the effect of endothelin receptors in chronic venous insufficiency （CVI） in lower extremities. Methods Ten eases of varicose veins from CVI patients （as ease group） and ten cases of non-varicose veins （as control group） were investigated in this study. The two groups were divided into two groups respectively： endothelium-intact group and de-endothelium groups. The vasoconstriction mediated by endothelin A （ETA） and endothelin B （ETB） receptors was recorded with myography. The distribution of ETA and ETB receptors was detected by immunohistoehemistry method. Results Endothelin-1 （ ET-1 ） and sarafotoxin 6c （ S6c ） induced concentration-dependent contraction in the veins. In endothelium-intaet veins, the Emax and pD2 of contraction curve induced by ET-1 were 132. 30% ±43.42% and 6.03 ±0.35, respectively in control group;and were 19.24% ± 12.94% and 6. 78 ±0.46, respectively in ease group. The Emax and pD2 in case group were much lower than in control group （P 〈0.05）. The Emax and pD2 induced by S6c were 30. 10% ± 12. 90% and 6.54 ±0.36, respectively in control group, and were 9. 61% ± 1.32% and 6. 75 ±0. 29, respectively in case group; The Emax in case group was lower than in control group （P 〈 0. 05）. In de-endothelium veins, Emax and pD2 of S6c were 146. 18% ± 32. 33% and 6. 50 ± 0. 17 in control group, and 32. 93% ± 3.00% and 6. 69 ± 0. 39 in case group; The Emax in case group was significantly lower than in control group （P 〈0.05）. ETA receptors was located in endothelium mainly, and ETB receptors in smooth muscle cells mainly. The sites of both ETA and ETB receptors were decreased in case group obviously. Conclusions The contraction mediated by ETA receptor and ETB receptor was decreased with a decrease of ETA receptor and ETB receptor sites in varicose veins of CVI. The contraction insufficiency and down-expression of ETA receptor and ETB receptor are correlated with CVI.