Relationship between plasma norepinephrine and sympathetic neural activity.

摘要: For circulating norepinephrine (NE) to reflect sympathetic activity validly, plasma NE should show an intensity-dependent increase during stimulation and decrease inhibition, correlate with more directly obtained measures of activity. Review published evidence indicates that in peripheral satisfies these criteria. However, models used explain the relationship between must take into account processes intervening synaptic cleft free circulation and, since outflow is regionalized, contributions specific vascular beds NE. In this report a model presented where removal for are viewed as acting series produce gradient concentrations from synapse plasma, relative calculated arteriovenous difference across those percentage cardiac output distributed them. general, venous provides useful estimation average outflow.