Electrochemical and electrophysiological characterization of neurotransmitter release from sympathetic nerves supplying rat mesenteric arteries

Abstract

1. Characteristic features of noradrenaline (NA) and adenosine 5'-triphosphate (ATP) release from postganglionic sympathetic nerves in rat small mesenteric arteries in vitro have been investigated on an impulse-by-impulse basis. NA release was measured using continuous amperometry and ATP release was monitored by intracellular recording of excitatory junction potentials (e.j.ps). 2. Electrical stimuli evoked transient increases in oxidation current. During trains of ten stimuli at 0.5-4 Hz there was a depression in the amplitude of oxidation currents evoked following the first stimulus in the train. 3. The neuronal NA uptake inhibitor, desmethylimipramine (1 μM), increased the amplitude of t..