Cardiac Regenerative Potential of Spiny Mice (Acomys cahirinus) Manifests Itself in Expansion of Pacemaker Myocardium and Predominance of Noncanonical, IK, ACH-Independent Pathway of Cholinergic Regulation in Cardiac Pacemaking

Doklady Biological Sciences. 2025. Vol. 520. P. 73–79.

Kuzmin V. S., Egorov Y. V., Karhov A. M., M. A. Boldyreva, Parfyonova E. V.

 Spiny mice (Acomys cahirinus) exhibit the ability to regenerate the damaged myocardium and functionalindices of the heart. demonstrated in various models of cardiac pathologies. Cardioregenerative potentialof Acomys is associated with partial preservation of the neonatal phenotype of cardiac tissue in adult animals.The electrophysiology and mechanisms regulating the heart rhythm in Acomys are extremely poorlyunderstood. The EEG was recorded in vivo and bioelectrical activity of the supraventricular myocardium wasevaluated and mapped in spiny mice. Pacemaker-type action potentials were detected in a significant part ofthe right atrium, and primary activation involved approximately 41% of the atrium surface in Acomys. Cholinergicstimulation caused pronounced suppression of automaticity and changed the activation pattern of thepacemaker myocardium. IKAch-independent mechanisms mediated the cholinergic inhibition of automaticityin Acomys. Thus, the cardioregenerative potential of spiny mice manifests itself in delocalization andnonclassical regulation of the cardiac pacemaker.

Keywords: regeneration, automaticity, spiny mice, neonatal phenotype, cholinergic regulation, sinus node, cardiac pacemaker, Acomys