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Updated: Jul 30, 2026

En Face Detection of Nitric Oxide and Superoxide in Endothelial Layer of Intact Arteries
Published on: February 25, 2016
Nitric oxide as an inhibitory non-adrenergic non-cholinergic neurotransmitter
H Bult1, G E Boeckxstaens, P A Pelckmans
1Division of Pharmacology, Faculty of Medicine, University of Antwerp (UIA), Wilrijk, Belgium.
Abstract:
Inhibitory non-adrenergic non-cholinergic (NANC) nerves are thought to be important in the autonomic innervation of the gastrointestinal tract and other organ systems. The nature of their neurotransmitter is still debated. Speculation that nitric oxide (NO), formed from L-arginine in neuronal structures and other cells, could act as a neurotransmitter, is not yet supported by demonstration of its release upon nerve stimulation. Using a superfusion bioassay, we report the release of a vasorelaxant factor upon stimulation of the NANC nerves in the canine ileocolonic junction. Several pieces of evidence, including the selectivity of the bioassay tissues, chemical instability, inactivation by superoxide anion and haemoglobin, inhibition by NG-nitro-L-arginine (L-NNA) and potentiation by L-arginine all indicated that NO accounted for the biological activity of this transferable NANC factor.
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