In Vitro Study of the Effects of Leu-Enkephalin and Related Drugs on the Vagally Induced Responses of the Cat Lower Esophageal Sphincter
The lower esophageal sphincter (LES) has a double extrinsic innervation (parasympathetic and sympathetic). The parasympathetic pathway running in the vagus nerves is composed of cholinergic preganglionic fibers connected either with excitatory cholinergic intramural neurons or with inhibitory non-adrenergic non-cholinergic neurons (1, 2). In physiological conditions the inhibitory vagal pathway is involved in the LES opening during swallowing and secondary esophageal peristalsis; the excitatory vagal pathway probably participates in the closure observed afterwards and in the maintenance and reflex modulation of resting tone (2, 3).
KeywordsVagus Nerve Lower Esophageal Sphincter Gastrointestinal Motility Opiate Receptor Excitatory Response
Unable to display preview. Download preview PDF.
- 1.Gonella, J., Niel, J.P. and Roman, C. (1977). Vagal control of lower oesophageal sphincter motility in the cat. J. Physiol. ( London ), 273, 647–664.Google Scholar
- 2.Roman, C. and Gonella, J. (1981). Extrinsic control of digestive tract motility. In: Johnson, L.R. (ed). Physiology of the gastrointestinal tract. pp. 289–333. ( New York: Raven Press ).Google Scholar
- 3.Goyal, R.K. and Cobb, B.W. (1981). Motility of the pharynx, esophagus and esophageal sphincters. In: Johnson, L.R. (ed). Physiology of the gastrointestinal tract. pp. 359–391. ( New York: Raven Press ).Google Scholar
- 4.Uddman, R., Alumets, J., Hakanson, R., Sundler, F. and Walles, B. (1980). Peptidergic ( Enkephalin) innervation of the mammalian esophagus. Gastroenterol., 78, 732–737.Google Scholar
- 5.Rattan, S. and Goyal, R.K. (1983). Identification and localization of opioid receptors in the opossum lower esophageal sphincter. J. Pharmacol. exp. therap., 224, 391–397.Google Scholar
- 8.Gonella, J. (1972). Modifications of electrical activity of the rabbit duodenum longitudinal muscle after contractions of the circular muscle. Am. J. Dig. Dis., 17, 327–332.Google Scholar
- 9.Furness, J.B., Costa, M., Franco, R. and Llewellyn-Smith, I.J. (1980). Neuronal peptides in the intestine: distribution and possible functions. In: Costa, M. and Trabucchi, M. (eds). Neural peptides and neuronal communication. pp. 601–617 ( New York: Raven Press ).Google Scholar