title: The release of endogenous acetylcholine from the medial septum/diagonal band of rat brain.
abstract: This study sought to establish whether cholinergic neurons in the medial septum/vertical limb of the diagonal band (ms/vdB) release endogenous acetylcholine (ACh) locally, and whether the release was modulated by presynaptic feedback mechanisms. Release of ACh from slices of the ms/vdB was assessed by gas chromatography-mass spectrometry (GC-MS). Potassium depolarization resulted in a 20- to 25-fold increase in ACh release above spontaneous levels. Omission of Ca2+ from the incubation medium decreased this release by 91%. In the presence of 4 microM atropine, potassium-induced ACh release was enhanced by 48%. These results indicate that ACh is released in the ms/vdB by a Ca2+-dependent and atropine-sensitive process.
authors.affiliation: Department of Pharmacology, Queen's University, Kingston, Ont., Canada.
authors.forename: R H
authors.initials: RH
authors.lastname: Metcalf
authors.forename: R J
authors.initials: RJ
authors.lastname: Boegman
authors.forename: R J
authors.initials: RJ
authors.lastname: Riopelle
authors.forename: S K
authors.initials: SK
authors.lastname: Ludwin
mesh_terms: D000109:Acetylcholine / Q000378:metabolism*; D000818:Animals; D001285:Atropine / Q000494:pharmacology; D002118:Calcium / Q000502:physiology; D002795:Choline O-Acetyltransferase / Q000378:metabolism; D005625:Frontal Lobe / Q000187:drug effects / Q000378:metabolism*; D066298:In Vitro Techniques; D008297:Male; D051381:Rats; D011919:Rats, Inbred Strains; D012686:Septal Nuclei / Q000187:drug effects / Q000378:metabolism*
chemical_list: D001285:Atropine; D002795:Choline O-Acetyltransferase; D000109:Acetylcholine; D002118:Calcium