Role of Nitric Oxide in Central Sympathetic Outflow
Kaushik P. Patel*,1, Yi-Fan Li* and Yoshitaka Hirooka
* Department of Physiology and Biophysics, University of Nebraska Medical Center, 984575 Nebraska Medical Center, Omaha, Nebraska 68198-4545; and
Department of Cardiovascular Medicine, Graduate School of Medical Sciences, Kyushu University, Fukuoka 812-8582, Japan
The gaseous molecule nitric oxide (NO) plays an important role
in cardiovascular homeostasis. It plays this role by its action
on both the central and peripheral autonomic nervous systems.
In this review, the central role of NO in the regulation of
sympathetic outflow and subsequent cardiovascular control is
examined. After a brief introduction concerning the location
of NO synthase (NOS) containing neurons in the central nervous
system (CNS), studies that demonstrate the central effect of
NO by systemic administration of NO modulators will be presented.
The central effects of NO as assessed by intracerebroventricular,
intracisternal, or direct injection within the specific central
areas is also discussed. Our studies demonstrating specific
medullary and hypothalamic sites involved in sympathetic outflow
are summarized. The review will be concluded with a discussion
of
the role of central NO mechanisms in the altered sympathetic outflow in disease states such as hypertension and heart failure.