Luu T N, Chester A H, O'Neil G S, Tadjkarimi S, Yacoub M H
National Heart and Lung Institute, Harefield Hospital, Middlesex.
Br Heart J. 1992 Jun;67(6):474-7. doi: 10.1136/hrt.67.6.474.
To assess the role of neuropeptides in the control of vascular tone in the human saphenous vein the actions of substance P, vasoactive intestinal peptide, calcitonin gene related peptide, neuropeptide Y, and somatostatin on this blood vessel were examined.
In vitro organ bath techniques were used with preparations of saphenous veins obtained from 29 patients (aged 41-66) who were undergoing coronary bypass surgery.
Substance P, vasoactive intestinal peptide, and calcitonin gene related peptide relaxed pre-constricted vessels in a dose dependent manner with a rapid onset of action, taking one to two minutes to reach a plateau at each dose. Substance P (10(-9) to 10(-6) mol/l) induced relaxation with a maximum response (mean (SEM)) 23.0 (6.6)% of the total relaxation induced by glyceryl trinitrate 1 microgram/ml and a 50% maximal effective concentration of 6.8 x 10(-9) mol/l. Vasoactive intestinal peptide (10(-10) to 10(-7) mol/l) produced a relaxation of 27.0 (5.1)% at 10(-7) mol/l. The maximum responses induced by substance P and vasoactive intestinal peptide were significantly reduced, to 3.7 (2.8)% and 4.7 (2.0)% respectively, after removal of the endothelium. Calcitonin gene related peptide (10(-10) to 10(-7) mol/l) elicited only 14.3 (2.6)% relaxation at 10(-7) mol/l, and this was not affected by removal of the endothelium. By contrast, neuropeptide Y and somatostatin exerted concentration dependent constriction on resting vessels. Neuropeptide Y (10(-10) to 10(-7) mol/l) caused prolonged contraction (roughly 20 minutes to reach a maximum plateau at each dose). At 10(-7) mol/l, the constriction amounted to 28.0 (12.0)% of the response to 90 mM KCl, in ring segments with or without endothelium. Somatostatin (10(-10) to 10(-6) mol/l) quickly caused contraction with a maximum response of 42.7 (15.0)% and a maximum response of 42.7 (15.0)% and a 50% maximal effective concentration of 6.7 x 10(-6) mol/l. The constriction was greatly increased when endothelium was removed, with a maximum response of 78.2 (16.8)% and a 50% maximal effective concentration of 4.3 x 10(-7) mol/l.
Vasoactive peptides have diverse effects on the vascular tone these effects are endothelium dependent. The exact physiological role and implication for performance of bypass grafts require further investigation.
评估神经肽在控制人体大隐静脉血管张力中的作用，研究P物质、血管活性肠肽、降钙素基因相关肽、神经肽Y和生长抑素对该血管的作用。
采用体外器官浴技术，使用从29例（年龄41 - 66岁）接受冠状动脉搭桥手术患者获取的大隐静脉标本。
P物质、血管活性肠肽和降钙素基因相关肽以剂量依赖性方式使预收缩血管舒张，起效迅速，每剂1 - 2分钟达到平台期。P物质（10⁻⁹至10⁻⁶mol/L）诱导舒张，最大反应（均值（标准误））为硝酸甘油1μg/ml诱导的总舒张的23.0（6.6）%，50%最大有效浓度为6.8×10⁻⁹mol/L。血管活性肠肽（10⁻¹⁰至10⁻⁷mol/L）在10⁻⁷mol/L时产生27.0（5.1）%的舒张。去除内皮后，P物质和血管活性肠肽诱导的最大反应分别显著降低至3.7（2.8）%和4.7（2.0）%。降钙素基因相关肽（10⁻¹⁰至10⁻⁷mol/L）在10⁻⁷mol/L时仅引起14.3（2.6）%的舒张，且不受去除内皮的影响。相比之下，神经肽Y和生长抑素对静息血管施加浓度依赖性收缩。神经肽Y（10⁻¹⁰至10⁻⁷mol/L）引起长时间收缩（每剂约20分钟达到最大平台期）。在10⁻⁷mol/L时，无论有无内皮的环段中，收缩幅度达90mM氯化钾反应的28.0（12.0）%。生长抑素（10⁻¹⁰至10⁻⁶mol/L）迅速引起收缩，最大反应为42.7（15.0）%，50%最大有效浓度为6.7×10⁻⁶mol/L。去除内皮后收缩显著增强，最大反应为78.2（16.8）%，50%最大有效浓度为4.3×10⁻⁷mol/L。
血管活性肽对血管张力有多种作用，这些作用依赖于内皮。其确切的生理作用及对旁路移植物性能的影响需要进一步研究。
