Over the past several decades, studies of the sympathetic nervous system in humans, sheep, rabbits, rats, and mice have substantially increased mechanistic understanding of cardiovascular function and dysfunction. Recently, interest in sympathetic neural mechanisms contributing to blood pressure control has grown, in part because of the development of devices or surgical procedures that treat hypertension by manipulating sympathetic outflow. Studies in animal models have provided important insights into physiological and pathophysiological mechanisms that are not accessible in human studies. Across species and among laboratories, various approaches have been developed to record, quantify, analyze, and interpret sympathetic nerve activity (SNA). In general, SNA demonstrates “bursting” behavior, where groups of action potentials are synchronized and linked to the cardiac cycle via the arterial baroreflex. In humans, it is common to quantify SNA as bursts per minute or bursts per 100 heart beats. This type of quantification can be done in other species but is only commonly reported in sheep, which have heart rates similar to humans. In rabbits, rats, and mice, SNA is often recorded relative to a maximal level elicited in the laboratory to control for differences in electrode position among animals or on different study days. SNA in humans can also be presented as total activity, where normalization to the largest burst is a common approach. The goal of the present paper is to put together a summary of “best practices” in several of the most common experimental models and to discuss opportunities and challenges relative to the optimal measurement of SNA across species.
|Original language||English (US)|
|Journal||American Journal of Physiology - Heart and Circulatory Physiology|
|State||Published - May 15 2017|
Bibliographical noteFunding Information:
This work was funded by National Heart, Lung, and Blood Institute Grants HL-83947 (to N. Charkoudian, B. G. Wallin, and E. C. Hart) and HL-122919 (to J. R. Carter). C. N. May’s laboratory was supported by National Health and Medical Research Council of Australia Grant 1050268 and the Victorian Government’s Operational Infrastructure Support Program.
© 2017 the American Physiological Society.
- Autonomic nervous system
- Blood pressure
- Nerve recording