ALPHA-BUNGAROTOXIN-SENSITIVE AND METHYLLYCACONITINE-SENSITIVE NICOTINIC RECEPTORS MEDIATE FAST SYNAPTIC TRANSMISSION IN INTERNEURONS OF RATHIPPOCAMPAL SLICES

This study demonstrates for the first time that alpha 7 nicotinic rece ptors (nAChRs) mediate fast synaptic transmission in conventional hipp ocampal slices. In the presence of antagonists of muscarinic, AMPA, NM DA, GABA(A), ATP, and 5-HT3 receptors, spontaneous and evoked postsyna ptic currents (PSCs) recorded from CA1 interneurons were blocked by th e alpha 7 nAChR antagonists methyllycaconitine and alpha-bungarotoxin and by a desensitizing concentration of the alpha 7 nAChR agonist chol ine. Spontaneous nicotinic PSCs were also accompanied by Na+ transient s, indicating that alpha 7 nAChR-mediated transmission serves as an ex citatory signal to the CA1 interneurons in the hippocampus. (C) 1998 E lsevier Science B.V. All rights reserved.