感觉神经肽与支气管对肺动脉缺氧反应的影响

豚鼠离体肺动脉用辣椒素（Ｃａｐｓａｉｃｉｎ）耗竭感觉神经肽（ＳＮＰ）后，缺氧性收缩反应（ＨＰＶ）显著增高（Ｐ＜０．０１）。套有带完整上皮支气管的肺动脉的ＨＰＶ显著弱于不套或套有去上皮支气管肺动脉的ＨＰＶ（Ｐ＜０．０５）；支气管与肺动脉同时用Ｃａｐ处理后，此差异消失；只有外套的支气管先用Ｃａｐ预处理时，肺动脉ＨＰＶ仍显著强于溶剂预处理的对照组（Ｐ＜０．０５）；套有去上皮支气管的肺动脉缺氧反应显著强于不套支气管的肺动脉。结果提示：肺动脉Ｃ－感觉神经所释放的ＳＮＰ在肺动脉缺氧反应中具调节作用；支气管上皮层可释放舒血管物质调节ＨＰＶ，此物质与ＳＮＰ密切相关；支气管还可能释放缩血管物质，介导ＨＰＶ。

EFFECT OF SENSORY NEUROPEPTIDES AND BRONCHI ON HYPOXIC PULMONARY VASOCONSTRICTION

After depleting the sensory neuropeptide (SNP) with capsaicin, the responses of pulmonary arteries of guinea pig to hypoxia (HPV)increased markedly ( P <0.01). The HPV of guinea pig pulmonary arteries coated with bronchus of intact epithelium was much lower than that of those not coated with bronchus or coated with epithelium denuded bronchus ( P <0. 05), these differences disappeared after the treatment of capsaicin. If the pulmonary artery was coated with an bronchus of intact epithelium pretreated with capsaicin, it responsed to hypoxia more strongly than coated group of which the bronchus was treated with vehicle( P <0.05). The HPV of the pulmonary arteries coated with epithelium denuded bronchus appeared stronger than HPV of those uncoated with bronchus. It is suggested that SNP released from C sensory nerves in pulmonary arteries and bronchi could modulate the hypoxic pulmonary vasocontriction, and the relaxant factors released from bronchial epithelium which relaxed pulmonary arteries and modulated HPV, are related to SNP. Furthermore, some vasoconstrictive factors might be released from hypoxic bronchi as well.