title: Bispyridinium non-oximes: An evaluation of cardiac effects in isolated hearts and smooth muscle relaxing effects in jejunum.
abstract: Bispyridinium non-oximes seem to be promising candidates for the generic treatment of nerve agent poisoning as they interact with nicotinic and muscarinic acetylcholine receptors. The lead compound MB327 showed therapeutic effectiveness in vitro and in vivo but was toxic at higher doses. In the present study, the effect of various bispyridinium non-oximes on isolated heart and small intestine function was investigated. Bispyridinium non-oximes and oximes were tested in at least seven different concentrations in rat jejunum preparations pre-treated with carbachol. All bispyridinium non-oximes showed classical dose response curves with MB327 being the most effective (EC50=6.6μM) and MB782 being slightly less effective (EC50=10.4μM). Neither the bispyridinium non-oximes nor the oximes showed cardiotoxic effects in the isolated Langendorff heart. The tested bispyridinum compounds showed no direct cardiac effect but had variable smooth muscle relaxing effects. Further in vivo studies are required to get more insight into potential toxic mechanisms of these promising nerve agent antidotes.
authors.affiliation: Bundeswehr Institute of Pharmacology and Toxicology, Neuherbergstr. 11, 80397, Munich, Germany.
authors.forename: Katharina
authors.initials: K
authors.lastname: Neumaier
authors.affiliation: Bundeswehr Institute of Pharmacology and Toxicology, Neuherbergstr. 11, 80397, Munich, Germany.
authors.forename: Franz
authors.initials: F
authors.lastname: Worek
authors.affiliation: Bundeswehr Institute of Pharmacology and Toxicology, Neuherbergstr. 11, 80397, Munich, Germany.
authors.forename: Horst
authors.initials: H
authors.lastname: Thiermann
authors.affiliation: Bundeswehr Institute of Pharmacology and Toxicology, Neuherbergstr. 11, 80397, Munich, Germany. Electronic address: timowille@bundeswehr.org.
authors.forename: Timo
authors.initials: T
authors.lastname: Wille
mesh_terms: D000818:Animals; D000931:Antidotes / Q000494:pharmacology*; D006321:Heart / Q000187:drug effects* / Q000502:physiology; D066298:In Vitro Techniques; D007583:Jejunum / Q000187:drug effects* / Q000502:physiology; D008297:Male; D009126:Muscle Relaxation / Q000187:drug effects; D009130:Muscle, Smooth / Q000187:drug effects / Q000502:physiology; D010091:Oximes / Q000494:pharmacology*; D011726:Pyridinium Compounds / Q000494:pharmacology*; D017208:Rats, Wistar
chemical_list: D000931:Antidotes; D010091:Oximes; D011726:Pyridinium Compounds
keywords: Bispyridinium non-oximes; Cardiac; Isolated heart; Oximes; Smooth muscle function