Pharmacological analysis of nerves supplying the oesophagus.

Morphological studies indicate that cholinergic, peptidergic and "nitrergic" (nitric oxide releasing) nerves supply the oesophageal muscle. In the present in vitro study, intramural nerves of guinea pig and human oesophagus were activated by means of the ganglion stimulating drug nicotine and electrical field stimulation (EFS) in organ bath experiments. In general, stimulation-induced primary contractions were diminished by atropine, while non-adrenergic, non-cholinergic (NANC) relaxations and after-contractions were inhibited by the NO-synthase inhibitor NG-nitro-L-arginine (L-NNA). Thus we obtained pharmacological evidence for cholinergic muscarinic, as well as nitric oxide mediated mechanisms in the functional innervation of the oesophageal muscle.