血管舒缩

The balance of vasoconstrictor and vasodilator can maintain normal tension of blood vessel.

正常的血管张力要靠缩血管因子和舒血管因子之间的平衡来维护。

In physiolgoical state,the action of traditional RAAS on blood pressure might be decreased with age in aged people,and the vasoactive peptides might contribute more to the cardiovascular action to keep blood pressure stable. Activity of vasoconstrictive peptides were incresaed and activity of vasodilative peptide was decreased.

老年人随着年龄的增长，在生理状态下传统的RAAS的作用减弱，更多的是血管活性肽(ANP，ET，CGRP)参与心血管活性的调节，老年EH患者缩血管肽ET的活性增高、舒血管肽CGRP活性减弱。

The gaseous monoxides nitric oxide and carbon monoxide, generated within the blood vessel wall, have been identified as important cellular messengers involved in the regulation of intracellular cGMP levels, platelet aggregation and smooth muscle relaxation, The mechanism by which carbon monoxide activates soluble guanylyl cyclase is similar to that of nitric oxide, and involves binding and dislocation of its heme-iron to induce a conformational change and activation of the catalytic site of guanylyl cyclase.

一氧化氮是体内最重要的气体信使分子，不仅是维持血管正常舒缩功能的重要介质，而且还有抑制单核细胞及血小板与内皮的粘附、聚集、抑制血管平滑肌细胞的增殖等作用。近年研究表明，内源性一氧化碳是体内另一个重要的气体信使分子，它是由血红素氧合酶氧化分解血红素产生的，具有与一氧化氮相似的生理功能。

Result :(1)the percentage of NTG tolerance in Group Ⅱ and Group Ⅲ were lower than that of Group Ⅰ( P ＜0.05);(2)Captopril and non-sulfhydryl ACEI could inhibit the re-elevation of SBP and the decrease of platelet cGMP at the later stage during the NTG infusion;(3)Platelet cGMP could be an indicator of nitrate tolerance;(4)ACEI could decrease the production of vasoconstrictor substances such as Ang Ⅱ,ET and increase the production of vasorelaxant substances such as BK.

结果：①Ⅱ组和Ⅲ组耐药比例均较Ⅰ组低( P ＜0.05)；②加用Captopril和非巯基ACEI能使NTG滴注过程后期的SBP回升及血小板cGMP下降得到抑制；③血小板cGMP能反映NTG耐药；④ACEI能在NTG滴注过程中使缩血管物质减少、舒血管物质增多。

Do you know, i need you to come back

你知道吗，我需要你回来

Yang yinshu、Wang xiangsheng、Li decang,The first discovery of haemaphysalis conicinna.

1〕 杨银书，王祥生，李德昌。安徽省首次发现嗜群血蜱。