An Investigation to Assess Tacrolimus-Induced Cardiotoxicity in Rats: Functional, Biochemical, and Histopathological Insights

Background and objective: Tacrolimus is an immunosuppressant that is widely used in allograft recipients. However, on chronic use, it appears to have side effects. Reports included cardiotoxicity, which has not been fully investigated. This study aimed to examine its cardiotoxicity on functional, biochemical, and histopathological insights. Methods: Eight male albino rats, weighing 150 -200 g, were divided into two groups. The control group received intraperitoneal (i.p.) saline while Tacrolimus-treated group received i.p. Tacrolimus (2 mg/kg) daily for 14 consecutive days. Cardiac functions including Echocardiograms, serum cardiac enzymes (CK-MB and LDH), myocardial histopathology examination by H&E and Masson’s trichome stains and myocardial cleaved caspase-3 immunohistochemistry content were assessed. Results: The results showed features of cardiac injury signified as hypertrophy by echocardiogram, elevated serum CK-MB and LDH levels, myocardial tissue damage with H&E stain, fibrotic changes by Masson trichome stain and elevated cleaved caspase-3 immune reactivity. Conclusion: Tacrolimus exerts myocardial damage with 2 weeks treatment appeared as hypertrophy mediated by fibrosis and apoptosis.