Laughlin M H
Department of Veterinary Biomedical Sciences, Dalton Cardiovascular Research Center, University of Missouri, Columbia 65211, USA.
Med Sci Sports Exerc. 1995 Aug;27(8):1135-44.
The purpose of this paper is to examine the role of endothelium-derived relaxing factors in the control of coronary vascular resistance in conditioned subjects (i.e., after exercise training for a period of time sufficient to complete adaptation processes). Results from studies with exercise trained (EX) dogs, miniature swine, and rats are summarized. Since the relative importance of vascular control mechanisms differ in various segments of the coronary arterial tree, the effects of EX on conduit arteries and the coronary arterial microcirculation are discussed separately. Results indicate that endothelium-mediated vasodilator responses are normal in conduit coronary arteries of EX dogs, miniature swine, and rats. It is proposed that endothelium-mediated vasodilation of conduit coronary arteries is enhanced early in the exercise-adaptive process but returns to normal as adaptation to EX is complete, when structural adaptations produce a relative decrease in coronary shear during exercise. EX miniature swine manifest enhanced endothelium-mediated vasodilation stimulated by bradykinin and flow in isolated coronary resistance arteries and appear to have increased expression of NO synthase (ecNOS). Brief training also appears to increase the expression of ecNOS. The role of endothelium-mediated vasodilation in regulation of coronary blood flow in EX animals remains uncertain.
本文旨在研究内皮源性舒张因子在调控适应训练个体（即经过一段足以完成适应过程的运动训练后）冠状动脉阻力中的作用。总结了对运动训练（EX）后的犬、小型猪和大鼠的研究结果。由于冠状动脉树各节段血管控制机制的相对重要性不同，因此分别讨论了EX对传导动脉和冠状动脉微循环的影响。结果表明，EX犬、小型猪和大鼠的传导冠状动脉中，内皮介导的血管舒张反应正常。有人提出，在运动适应过程早期，传导冠状动脉的内皮介导血管舒张增强，但随着对EX适应的完成，当结构适应导致运动期间冠状动脉剪切力相对降低时，其会恢复正常。EX小型猪在离体冠状动脉阻力动脉中表现出由缓激肽和血流刺激的增强的内皮介导血管舒张，并且似乎一氧化氮合酶（ecNOS）的表达增加。短期训练似乎也会增加ecNOS的表达。内皮介导的血管舒张在EX动物冠状动脉血流调节中的作用仍不确定。
