[Reaction of population of pulmonary mast cells in rat bronchial asthma under the effect of ß-adrenoreceptor antagonists].

Multifunctional granular mast cells (MCs) are among targets in bronchial asthma (BA) therapy. We studied pulmonary MC population in a rat model of BA under the effect of ß-adrenoreceptor antagonists and of the latter combined with the standard therapy (glucocorticoid budesonide + ß2-adrenergic agonist salbutamol). MCs of different degrees of maturity were identified on paraffin section of lung stained with Alcian blue and Safranin. MC density in the lung of rats with BA increased 1.9 times. Alcian blue-positive immature cells predominated in the lungs of both intact rats and rats with BA. In response to pharmacological agents, the mean MC densities were reduced in 2-2.7 times in all the variants of experiments and were close to the norm. It allows us to suppose that MCs migration from the outside was suppressed and, in consequence of the decline of MC densities, the release of the mediators involved in the progression of BA may be diminished.

[Efferent innervation of pulmonary blood vessels and bronchi in rat (an immunohistochemical study)].

In this investigation the peculiarities of innervation of bronchi and blood vessels of the lung were studied in 20 rats using immunohistochemical demonstration of synaptophysin and alpha-actin. The results obtained have showen that the densest innervation is typical for bronchial walls, particularly, for the muscular lamina. Synaptophysin-immunoreactive terminals (SFIT) were detected in the bronchi in close association with both circular bundles of smooth muscle cells and microganglia. Dense network of SFIT was found in the pulmonary vein--in its middle tunic formed by cardiomyocytes. In contrast to the bronchi and pulmonary vein, large branches of the pulmonary artery contained no SFIT. We briefly discuss the problem of the origin of the nerve fibers described and their functions and suggest that SFIT are formed by efferent fibers (axons) of neurons arising from either the intrapulmonary parasympathetic ganglia.

[Innervation of cardiac muscle tissue in rat pulmonary veins].

The pulmonary vein (PV) of 16 adult male Wistar rat was studied using synaptophysin immunohistochemistry and staining with toluidine blue and hematoxylin. Its intrapulmonary trunk wall was found to have a unique structure. The middle tunic contained cross-striated muscle tissue that was identical to the cardiac muscle tissue in posterior wall of the myocardial atrium. The thickness of the muscular tunic increased with the increase of vein diameter. The thickest layer of cardiac muscle fibers was located in the orifice of the main trunk, and the thinnest - in the lateral veins (50-100 microm in diameter), carrying the arterial blood from the respiratory portion of pulmonary lobe. Along their whole length, cardiac muscle fibers are densely innervated. Efferent synaptophysin-positive endings of the terminal plexus were found to be tightly associated with cardiac muscle fibers, capillaries of the media in the area of PV orifice and vasa vasorum of the adventitia.