Overview

Central Nervous System Control of the Cardiovascular System

The brain Na,K-ATPases and their endogenous inhibitor, the brain ouabain-like substance (OLS), are critically important in the regulation of the sympathetic nervous system (the so-called "fight or flight" system) and cardiovascular system in at least two disease states: high blood pressure (hypertension) and congestive heart failure following myocardial infarction (CHF post MI). In each of these conditions, hyperactivity of the sympathetic nervous system occurs and is mediated by both the brain OLS and the brain renin-angiotensin system (RAS).

Sympathetic nervous system hyperactivity in turn leads to detrimental effects (high blood pressure, accelerated damage to the heart, and accelerated development of heart failure). The brain OLS appears to activate the brain RAS system because the effects of the OLS are abolished by specific RAS blockers applied in the brain. Yet the effects of an RAS product (ang II) are not inhibited at all by antagonists of the OLS system.

Our primary interest is determining the exact physiological functions of OLS receptors in the brain.