Cholinergic transmission in pancreatic ganglia of the cat

L. Sha, J. A. Love, R. C. Ma, J. H. Szurszewski

Research output: Contribution to journalArticlepeer-review

14 Scopus citations

Abstract

Although there is considerable evidence indicating the existence of important cholinergic neural regulation of pancreatic function, very little is known about the action of acetylcholine on pancreatic ganglion neurons. The present study was undertaken to determine the effect of pressure microejection of acetylcholine and muscarine on ganglion cell excitability of the cat pancreas. Recordings were made in vitro from ganglion neurons located in the head region of the pancreas. Acetylcholine evoked a fast- and a slow- developing membrane depolarization in the majority of neurons tested. A decrease in membrane input resistance accompanied the fast depolarizing response, whereas an increase in input resistance accompanied the slow depolarizing response. The fast response was mimicked by 1,1-dimethyl-4- phenylpiperazinium iodide and nicotine and antagonized by hexamethonium. The slow depolarizing response was mimicked by muscarine and antagonized by atropine and pirenzepine. The dependence of the slow depolarization on extracellular K+ and the distinct voltage dependence of the slow depolarization suggest that activation of muscarinic receptors was due to inactivation of I(M). The slow excitatory postsynaptic potential and associated increase in excitability evoked by repetitive nerve stimulation was partially cholinergic dependent in the majority of neurons tested. It was concluded that cholinergic transmission in cat pancreatic ganglia involves nicotinic and M1 receptors that mediate fast and slow synaptic transmission, respectively, and that activation of M1 receptors modifies the output firing frequency.

Original languageEnglish (US)
Pages (from-to)83-93
Number of pages11
JournalPancreas
Volume14
Issue number1
DOIs
StatePublished - Jan 1997

Keywords

  • Cat
  • Muscarinic potentials
  • Nicotinic potentials
  • Pancreas
  • Parasympathetic ganglia

ASJC Scopus subject areas

  • Internal Medicine
  • Endocrinology, Diabetes and Metabolism
  • Hepatology
  • Endocrinology

Fingerprint Dive into the research topics of 'Cholinergic transmission in pancreatic ganglia of the cat'. Together they form a unique fingerprint.

Cite this