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Comparative studies on cardiotoxicity of some anthracycline antitumor antibiotics
Abstract:
Isolated atria of guinea-pigs showed negative inotropic and negative chronotropic responses after violamycin B I (V), carminomycin (C) and daunomycin (D), respectively. The mean effective concentrations in reducing amplitude (IC50) were 5.9 x 10(-4) mol x 1(-1) for V and 1.3 x 10(-4) mol x 1(-1) for C and D. In rabbits, intravenous injections of different doses of the antibiotics twice weekly for one month produced histopathological alterations in the myocardial tissue, which were smaller after D than after C or V.
Insights
Violamycin BI, carminomycin, and daunomycin exhibit cardiotoxic effects, reducing atrial contractility and causing myocardial damage in animal models. Daunomycin demonstrated the least severe histopathological alterations in rabbit myocardial tissue.
Area of Science:
- Pharmacology
- Cardiology
- Toxicology
Background:
- Anthracycline antibiotics are widely used in cancer chemotherapy.
- Some anthracyclines are known to possess cardiotoxic properties.
- Understanding the cardiac effects of specific antibiotics is crucial for patient safety.
Purpose of the Study:
- To investigate the inotropic and chronotropic effects of violamycin BI, carminomycin, and daunomycin on isolated guinea-pig atria.
- To evaluate the cardiotoxicity of these antibiotics in a rabbit model following repeated intravenous administration.
Main Methods:
- Isolated guinea-pig atria were used to assess negative inotropic and chronotropic responses.
- Mean effective concentrations (IC50) for amplitude reduction were determined.
- Rabbits received intravenous injections of antibiotics twice weekly for one month to examine myocardial histopathology.
Main Results:
- Violamycin BI, carminomycin, and daunomycin induced negative inotropic and chronotropic responses in isolated atria.
- Effective concentrations (IC50) for amplitude reduction were 5.9 x 10(-4) mol/L for violamycin BI and 1.3 x 10(-4) mol/L for carminomycin and daunomycin.
- Histopathological alterations in rabbit myocardial tissue were observed, with daunomycin showing less severe changes compared to carminomycin and violamycin BI.
Conclusions:
- Violamycin BI, carminomycin, and daunomycin exhibit direct cardiotoxic effects on atrial function.
- Repeated administration of these antibiotics can lead to myocardial histopathological damage.
- Daunomycin appears to have a comparatively lower cardiotoxic profile in the studied rabbit model.