Blood platelets in experimental lung emphysema. Comparative analysis of the number and aggregation abilities of platelets in left and right ventricular blood of the heart.

Quantitative and morphological analyses (in SEM) of blood platelets collected from the left and right ventricles of the rat heart in the course of experimental lung emphysema were done. Platelet aggregation index was estimated, too. Emphysema was induced by a single intratracheal instillation of papain solution in a dose of 20 mg/kg b.w/1 ml PBS. The animals were sacrificed after 2 and 24 hours and 7, 14, 28 days later. Within 24 hours of the experiment a slight decrease was observed in the number of platelets in the blood collected from the left ventricle compared to the right one as well as to control animals. Also a reduction in platelet aggregation coefficient value was noted. However, in the later period of emphysema progression (after 7th day), a statistically significant increase was found in the number of blood platelets in the left ventricle. A relation was noted between quantitative changes of blood platelets and emphysema progression evaluated morphometrically. The ultrastructural examinations in SEM suggest the occurrence of platelet satellitosis in animals intratracheally injected with papain solution. The present results indicate the possibility of a significant contribution of blood platelets to the pathogenesis of experimental lung emphysema.