Morphometric evaluation of murine pulmonary mast cells in experimental hemorrhagic shock.

Respiratory failure resulting frequently in death is one of the complications in the course of post-hemorrhagic changes. A systemic inflammatory reaction plays a significant role in the pathogenesis of this syndrome. Mast cells also contribute to this effect. To broaden our knowledge of the pathogenesis of respiratory insufficiency, we evaluated morphometrically lung mast cells in hemorrhagically shocked rats. Lung sections were stained with alcian blue and safranin, and four separate locations were distinguished: under the lung pleura, around the bronchi and the large vessels, and in the interalveolar septa. A decrease in the area and volume of mast cells and an increase in their circularity index in interalveolar septa and around the bronchi was observed. An enlargement of mast cells around lung vessels was also found. There were no changes in the morphometric parameters of mast cells under pleura. The results suggest an activation and degranulation of mast cells and a role in the inflammatory process causing acute lung injury in hemorrhagic shock.