离体人肺血管对收缩剂效应的研究

Investigation Into the Contractile Profile of Human Pulmonary Vessels in Vitro

了解肺血管阻力改变的机制及血管活性药物对肺动脉（ＰＡ）和肺静脉（ＰＶ）的作用有重要的临床和药学价值。作者自１９９３年７月至１９９４年３月应用器官水浴测定了ＰＡ及ＰＶ对５种血管收缩剂的反应性。结果ＰＡ与ＰＶ的反应曲线相似。对血栓素（ＴＢ）及内皮素（ＥＴ）的开始反应浓度为１０^（－１０）ｍｍｏｌ／Ｌ，最大收缩反应ＴＢ达ＫＣｌ的１７５％，ＥＴ与ＫＣｌ相近。而对５－羟色胺（５ＨＴ）、组织胺（ＨＭ）和去甲肾上腺素（ＮＡ）开始反应浓度很高，５ＨＴ及ＮＡ为３×１０^（－８）ｍｍｏｌ／Ｌ，ＨＭ为１０~－６最大收缩反应仅达ＫＣｌ的５０％或更低。半数ＰＡ对５ＨＴ完全无反应。结果表明ＰＡ与ＰＶ对５种血管收缩剂反应性相似，ＴＢ与ＥＴ较其他３种药物血管收缩作用明显强大，ＴＢ最强。半数ＰＡ对５ＨＴ无反应可能系ＰＡ有多种５ＨＴ受体缘故。

It is clinically very important and pharmaceutically valuable to know the mechanism of the changing of pulmonary vascular resistance and the effect of vasoactive agents on pulmonary vessels. However,not much is known about the control of pulmonary vascular tone in the human lung. Very little systemic research work has been done on normal or diseased human pulmonary vessel rings. From July 1993 to March 1994,the authors tested the responses of normal pulmonary arteries and veins to 5 vasoconstrictors with organ bath. This is the first systemic and comparative work with five constrictors not only on pulmonary arteries but also veins. The response curves of PA and PV were of similar type. The response to thromboxane(TB) and endothelin (ET) started from 10-10 nM,the maximum response to TB was up to 175%of that to KCl,but ET was about 100%of that to KCl. The maximum response to 5-hydroxytiryptamine (5HT),histamine (HM) and noradrenaline (NA) was around or below 50%of that to KCl and started to respond at high concentration (5HT and NA 3×10-8 mM,HM-10-6 mM). Half of the PA did not respond to 5HT at all. The results showed that the response of PA and PV was similar to five agonists used in this test. TB and ET are more powerful vasoconstrictors than the three others. The most powerful vasoconstrictor for pulmonary vessels TB. The reason for half PA not responding to 5HT is probably a refiection of the heterogeneous population of 5HT receptors which mediate contraction in human PA.