RESUMO
BACKGROUND: In this study, the effects of levosimendan used in the treatment of acute congestive heart failure upon pulmonary fibrosis in rats induced with bleomycin (BL) were analyzed. METHODS: A total of 33 male Sprague-Dawley type rats were categorized into five groups randomly. About 2.5U/kg BL was intratracheally administered to the rats in the BL, BL+L1, BL+L2, and BL+L3 groups, and 0.9% saline was intratracheally administered at the same rate to the control group. 0.3, 1, and 3mg/kg levosimendan was intraperitoneally administered to the BL+L1, BL+L2, and BL+L3 groups, respectively. Blood and tissue samples were taken from the rats euthanized to determine the changes in erythrocyte enzyme activities and to conduct histopathological evaluations after 14 days. With values between 0 and 3, histopathological scoring damage was assessed by the presence of inflammation and fibrosis in a semiquantitative manner. RESULTS: Compared with those in the C group, glutathione reductase (GR) and Catalase (CAT) enzymes decreased in the BL group; compared with that in the BL group, GR increased in the BL+L1 and BL+L3 groups, 6-phosphogluconate dehydrogenase (6PGD) increased in the BL+L3 group, and CAT increased in the BL+L2 and BL+L3 groups (p<0.05). In the histopathological evaluation, fibrosis occurred in all rats in the BL group, and tissue damage was noticed to be generally less in the BL+L1, BL+L2, and BL+L3 groups (p<0.001). CONCLUSIONS: The results obtained from biochemical and histopathological evaluations indicate that levosimendan had an anti-fibrotic effect without a dose-dependent response on pulmonary fibrosis.