[A quantitative analysis of the mastocytes and eosinophilic granulocytes in the myocardium of Wistar rats chronically infected by Trypanosoma cruzi. A contribution to the knowledge of myocardial fibrosis].

We did mast cell and eosinophil granulocyte counts in the myocardium of forty chronic chagasic Wistar albino rats. We used 10 controls rats and 30 animals with late-stage (8th month) infection of São Felipe, Y and Colombian Trypanosoma cruzi strains, with variable degree of chronic myocarditis. We found chronic fibrosing myocarditis (fibrosis) in 40% of the infected animals. It was detected increased mast cell count in the chagasic rats associated with infection and not related with myocardial fibrosis. There was no increase in the eosinophil counts.