Dose-Dependent Effects of Subchronic Lead Exposure on the Right Atrium and Right Ventricle of Rats: An In Vitro Investigation
- PMID: 40676397
- DOI: 10.1007/s12012-025-10043-1
Dose-Dependent Effects of Subchronic Lead Exposure on the Right Atrium and Right Ventricle of Rats: An In Vitro Investigation
Abstract
Lead poisoning remains a significant threat to both human and animal health, with cardiovascular dysfunction being one of its primary adverse effects. This study aimed to investigate the function of the right atrium and right ventricle in 12-month-old male rats exposed to 5.5, 11, and 22.88 mg/kg body weight of lead acetate, injected intraperitoneally three times a week for six weeks. Lead exposure resulted in a reduction in blood pressure (11 mg/kg b.w.) and QRS amplitude, and a lowering of the isoelectric line. Lead exposure led to a dose-dependent shift in the myosin heavy chain (MHC) ratio toward the slower β-MHC isoform in the right ventricle, whereas no changes were detected in the right atrium. We observed a dose-dependent increase in myosin regulatory light chain phosphorylation in the right ventricle and a decrease in the right atrium. In the atria, both active and passive tensions were reduced, while no significant alterations were found in the right ventricle. However, a dose-dependent slowing of the action potential was found in both atrial and ventricular myocardium. Both the right atrium and right ventricle demonstrated responses to lead exposure; however, there was a mismatch between the alterations observed in atrial and ventricular parameters. These findings suggest that the atrial and ventricular myocardium adapt differently to lead exposure, with their responses varying depending on the specific dosage of lead consumed.
Keywords: Action potential; Atria; Cardiotoxicity; Lead; Myocardium contractility; Ventricles.
© 2025. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.
Conflict of interest statement
Declarations. Competing Interests: The authors declare no competing interests. Ethical Approval: The study was approved by the Ethics Committee of the Yekaterinburg Medical Research Centre for Prevention and Health Protection of Industrial Workers (Protocol No. 3, dated January 17, 2024) and was conducted in accordance with the European Parliament Directive 2010/63/EU and the US National Institutes of Health’s “Guide for the Care and Use of Laboratory Animals” (NIH Publication No. 85-23, revised 1996). All animal experiments complied with the ARRIVE (Animal Research: Reporting of in vivo Experiments) guidelines. Informed Consent: Not applicable.
References
-
- WHO. (2019). WHO. Lead poisoning and health. Retrieved January 9, 2020, from https://www.who.int/news-room/fact-sheets/detail/lead-poisoning-and-health
-
- Javorac, D., Tatović, S., Anđelković, M., Repić, A., Baralić, K., Djordjevic, A. B., Mihajlović, M., Stevuljević, J. K., Đukić-Ćosić, D., Ćurčić, M., Antonijević, B., & Bulat, Z. (2022). Low-lead doses induce oxidative damage in cardiac tissue: Subacute toxicity study in Wistar rats and Benchmark dose modelling. Food and Chemical Toxicology, 161, 112825. https://doi.org/10.1016/j.fct.2022.112825 - DOI - PubMed
-
- Liu, L., Xu, A., & Cheung, B. M. Y. (2025). Associations between lead and cadmium exposure and subclinical cardiovascular disease in U.S. adults. Cardiovascular Toxicology, 25(2), 282–293. https://doi.org/10.1007/s12012-024-09955-1 - DOI - PubMed - PMC
-
- Davuljigari, C. B., & Gottipolu, R. R. (2020). Late-life cardiac injury in rats following early life exposure to lead: Reversal effect of nutrient metal mixture. Cardiovascular Toxicology, 20(3), 249–260. https://doi.org/10.1007/s12012-019-09549-2 - DOI - PubMed
-
- Fioresi, M., Simões, M. R., Furieri, L. B., Broseghini-Filho, G. B., Vescovi, M. V. A., Stefanon, I., & Vassallo, D. V. (2014). Chronic lead exposure increases blood pressure and myocardial contractility in rats. PLoS ONE. https://doi.org/10.1371/journal.pone.0096900 - DOI - PubMed - PMC
MeSH terms
Substances
Grants and funding
LinkOut - more resources
Full Text Sources