title: Alteration of cholinergic pressor and antinociceptive responses in rats pretreated with the cholinergic toxin AF64A.
abstract: 1. In the present study, the pressor and antinociceptive effects of physostigmine and oxotremorine were investigated in rats injected with AF64A intracerebroventricularly. 2. Physostigmine (50-100 micrograms/kg, i.v.)-induced pressor responses were significantly lower in AF64A-injected rats compared with saline-injected animals, whereas oxotremorine (20-80 micrograms/kg, i.v.)-induced responses were found to be similar to those seen in the saline group. 3. The physostigmine (100 micrograms/kg, s.c.)-induced antinociceptive effect was totally abolished by AF64A treatment, but that of oxotremorine (30 micrograms/kg, s.c.) remained unchanged at the tail-flick test. 4. The results of this study present functional evidence for AF64A-produced substantial loss of cholinergic neurons involved in the regulation of blood pressure and nociception but not in postsynaptic muscarinic receptors.
authors.affiliation: Department of Pharmacology, Marmara University School of Medicine, Istanbul, Turkey.
authors.forename: T
authors.initials: T
authors.lastname: Tellioğlu
authors.forename: N
authors.initials: N
authors.lastname: Erin
authors.forename: S B
authors.initials: SB
authors.lastname: Akin
authors.forename: K
authors.initials: K
authors.lastname: Berkman
authors.forename: S
authors.initials: S
authors.lastname: Oktay
mesh_terms: D000698:Analgesia; D000818:Animals; D001362:Avoidance Learning / Q000187:drug effects*; D001388:Aziridines / Q000494:pharmacology*; D002794:Choline / Q000031:analogs & derivatives* / Q000494:pharmacology; D002800:Cholinesterase Inhibitors / Q000494:pharmacology; D005260:Female; D008297:Male; D018782:Maze Learning / Q000187:drug effects*; D018721:Muscarinic Agonists / Q000494:pharmacology; D009466:Neuromuscular Blocking Agents / Q000494:pharmacology*; D010095:Oxotremorine / Q000494:pharmacology; D010147:Pain Measurement; D010830:Physostigmine / Q000494:pharmacology; D051381:Rats; D017207:Rats, Sprague-Dawley
chemical_list: D001388:Aziridines; D002800:Cholinesterase Inhibitors; D018721:Muscarinic Agonists; D009466:Neuromuscular Blocking Agents; D010095:Oxotremorine; D010830:Physostigmine; C044894:ethylcholine aziridinium; D002794:Choline