Stellate ganglion stimulation with alpha and beta adrenergic blockade: Effect on lung lipids and compliance in cats

Abstract

Stellate ganglion stimulation (SGS) can alter lung lipids and reduce static lung compliance, although the mechanisms remain unclear. Phentolamine and propranolol were administered to anesthetized cats prior to stimulation in order to investigate SGS effects on lung lipids and compliance mediated via alpha and beta adrenergic pathways. Analysis of lung lavage revealed that SGS alone decreased cholesterol and the cholesterol/DSPC ratio which might be expected to decrease lung compliance. Alpha and beta blockade alone resulted in no changes from control in cholesterol or DSPC. Alpha blockade plus SGS yielded increased rather than decreased cholesterol and DSPC, while beta blockade prevented any change. A reduction in both static and dynamic lung compliance caused by SGS also was blocked by both alpha and beta blockade. Thus both the alpha and beta blockade prevented the SGS-induced decreases in cholesterol, cholesterol/DSPC ratio, and lung compliance. Furthermore, alpha blockade plus SGS resulted in increased TPL as well as cholesterol and DSPC. The data are consistent with the view that DSPC and cholesterol are released into the subphase by beta adrenergic mechanisms, and that their relative amounts may influence surface properties.