Age-related attenuation of parasympathetic control of the heart in mice.

The autonomic nervous system maintains homeostasis through the balance of the sympathetic nervous system (SNS) and parasympathetic nervous system (PSNS). Especially evident in the heart, maintenance of this balance is important for the control of heart rate, conduction, and contractility. It is known that aging, similar to various cardiovascular diseases, results in an increase in SNS activity and a decrease in PSNS activity, which may contribute to age-related cardiac dysfunction and remodeling.