Макро- и микрогемодинамика легких при экспериментальной тромбоэмболии легочной артерии в условиях блокады альфа- и бета-адренорецепторов

Abstract

The pulmonary microhemodynamics changes in the experimental pulmonary thromboembolism model were studied in acute experiments on anesthetized rabbits with isolated dual channels lungs perfusion in control and after the blockade of α-adrenoceptors with phentolamine and β-adrenoceptors with propranolol. In control animals, pulmonary embolism caused the increasing of the pulmonary artery pressure, pulmonary vascular resistance, and precapillary resistance as well as elevating of the capillary filtration coefficient and postcapillary resistance. Phentolamine caused the decrease of the pulmonary artery pressure, pulmonary vascular resistance, and precapillary resistance. After the propranolol injection, the changes in most of the investigated parameters were opposite comparing with their shifts after the blockade of α-adrenoceptors. In the last case, pulmonary thromboembolism caused less increasing of the pulmonary microcirculatory parameters. However, the capillary filtration coefficient was elevated more, then in the control animals. In case of pulmonary thromboembolism after the blockade of the β-adrenoceptors, the most of the hemodynamic parameters increased more, than after the blockade of α-adrenoceptors; in both cases the capillary filtration coefficient increased to the same level. The value of its changes is determined of the reciprocal interaction of the α- and β-adrenergic mechanisms of the regulation of the permeability of the endothelium of the pulmonary vessels.