title: The effects of some cholinesterase reactivators on contractility of the isolated guinea-pig heart atria.
abstract: The effect of eight monoquaternary and bisquaternary pyridine aldoxime cholinesterase reactivators was tested on isolated guinea-pig heart atria. 2. Acetylcholine and methylfurthretonium in concentrations ranging from 10(-7) M to 10(-5) M have negative inotropic effects in the electrically stimulated atria and negative chronotropic effects in the spontaneously beating atria. 3. In the presence of higher concentration of cholinesterase reactivators alone, the parameters of heart muscle contractility are significantly altered. 4. Cumulative dose-response curves of methylfurthretonium in the presence of reactivators in the range of concentrations from 10(-5) M to 10(-3) M are shifted parallelly to higher concentrations of the agonist.
mesh_terms: D000109:Acetylcholine / Q000494:pharmacology; D000818:Animals; D002801:Cholinesterase Reactivators / Q000494:pharmacology*; D004305:Dose-Response Relationship, Drug; D005663:Furans / Q000494:pharmacology; D006168:Guinea Pigs; D006325:Heart Atria / Q000187:drug effects; D008297:Male; D009200:Myocardial Contraction / Q000187:drug effects*; D011220:Pralidoxime Compounds / Q000494:pharmacology*; D000644:Quaternary Ammonium Compounds / Q000494:pharmacology
chemical_list: D002801:Cholinesterase Reactivators; D005663:Furans; D011220:Pralidoxime Compounds; D000644:Quaternary Ammonium Compounds; D000109:Acetylcholine