The aim of this study was to investigate the possible effects of ivabradine against doxorubicin (DOX)-induced cardiotoxicity in rats using hemodynamic parameters (electrocardiogram, heart rate (HR), and blood pressure), biochemical markers of oxidative stress, lactate dehydrogenase, aspartate transaminase, creatine kinase-MB, and histopathological analyses both in serum and tissue specimens. A total of 28 female rats were randomly assigned to 4 groups: (a) control (n = 6 rats), (b) DOX group (n = 7 rats), (c) DOX + ivabradine-treated group (n = 8 rats), and (d) ivabradine group (n = 7 rats). When the means of the four groups were compared, there was only a significant difference in the level of HR (p < 0.05). DOX treatment caused more HR elevation when compared to the control group, whereas ivabradine application after DOX treatment significantly reduced HR levels. Cardiomyocytes were revealed as normal histology in the light of both hematoxylin and eosin staining and immunostaining methods (caspase-3 and bcl-2) in all groups. The present study reported the therapeutic effects of ivabradine against DOX-induced cardiotoxicity accompanied by the hemodynamic and biochemical parameters.

Purpose: To explore the protective and curative effects of molsidomine (MOL) on doxorubicin (DOX)-induced cardiac damage in the in vivo rat heart. Methods: Forty rats were randomized into five groups (n = 8): (1) the control group; (2) the MOL group (10 mg/kg for 21 days); (3) the DOX group (a single dose of 20 mg/kg); (4) the DOX + MOL group (3 days after the single dose of DOX, 10 mg/kg MOL continued for 21 days), and (5) the MOL + DOX group (24 h after a 21-day regimen of 10 mg/kg MOL, a single dose of DOX). The rats were monitored for mean arterial blood pressure, heart rate, O₂ saturation, and electrocardiography. Heart tissue levels of malondialdehyde (MDA), superoxide dismutase (SOD), catalase (CAT), reduced glutathione (GSH), and nitric oxide (NO) were determined. Results: Blood pressure and O₂ saturation values indicated a significant decrease in the DOX group compared with the control group. T negativity was observed in 4 of 8 rats in the DOX group, in 1 of 8 rats in the DOX + MOL group, and in 4 of 8 rats in the MOL + DOX group. MDA levels were significantly higher in the DOX group. SOD, GSH, and NO levels were significantly lower in the DOX group compared with the other groups. There was no statistically significant difference in the CAT levels in any of the study groups compared with controls. DOX treatment induced morphological alterations, such as disorganization of cardiomyocytes, loss of myofibrils, and cytoplasmic vacuolization in the heart. On the other hand, histological damage was significantly reduced in the DOX + MOL and MOL + DOX groups. Conclusion: This study implies that there are cardioprotective effects of MOL on DOX-induced cardiotoxicity.