Faculty Collaboration Database

An intrinsic neural pathway for long intestino-intestinal inhibitory reflexes. Gastroenterology 1987 Mar;92(3):594-603

Date

03/01/1987

Pubmed ID

3028893

DOI

10.1016/0016-5085(87)90006-0

Scopus ID

2-s2.0-0023095135 (requires institutional sign-in at Scopus site)   37 Citations

Abstract

We studied the mechanisms of initiation and pathways for the propagation of intestino-intestinal inhibitory reflexes induced by close intraarterial injections of neostigmine in conscious dogs. Two or three T-shaped catheters were surgically implanted in the intestinal branches of the superior mesenteric artery to inject pharmacologic agents locally in 10-15-cm-long segments. Migrating myoelectric complexes were recorded by a set of 10 electrodes and strain-gauge transducers. Close intraarterial injection of neostigmine initiated strong contractions of long duration in the perfused segment that terminated phase III activity in progress 90-150 cm distal or proximal to the cannulated sites and stopped its further migration. Atropine or 4-diphenylmethoxy-N-methylpiperidine methiodide injected just before neostigmine administration through the same catheter blocked both the local contractile effects and the reflex inhibition of phase III activity. Pirenzepine or hexamethonium injected in a similar manner did not affect the local response to neostigmine but blocked the reflex inhibition of phase III activity. A transection and reanastomosis in the mid-small intestine blocked the reflex inhibition by close intraarterial injection of neostigmine beyond the transection site. Pirenzepine, atropine, or hexamethonium injected through a middle catheter also blocked the reflex inhibition of phase III activity beyond the site perfused with these cholinergic antagonists. Close intraarterial administration of 4-diphenylmethoxy-N-methylpiperidine methiodide at a middle site had no effect on reflex inhibition. We concluded that strong spasmodic contractions in the small intestine initiate an intestino-intestinal inhibitory reflex in both directions. This reflex is mediated through an intrinsic neural pathway involving nicotinic and M1 muscarinic receptors.

Author List

Frantzides CT, Sarna SK, Matsumoto T, Lang IM, Condon RE

Author

Ivan M. Lang DVM, PhD Adjunct Professor in the Medicine department at Medical College of Wisconsin

MESH terms used to index this publication - Major topics in bold

Animals
Dogs
Female
Gastrointestinal Motility
Intestine, Small
Male
Muscle Contraction
Muscle, Smooth
Neostigmine
Neural Pathways
Receptors, Muscarinic
Receptors, Nicotinic
Reflex
Synaptic Transmission