Pharmacologic, electrical, or surgical regulation of sympathetic neuronal control can be used to modulate cardiac function and treat arrhythmias. However, current methods for monitoring sympathetic release of norepinephrine in the heart are limited in spatial and temporal resolution. Here, we provide for the first time, a methodology and demonstration of practice, rapid measures of individualized regional autonomic neurotransmitter levels in a beating heart. We show dynamic, spatially-resolved release profiles under normal and pathological conditions.
