title: The effect of the calcium antagonist nimodipine on the detoxification of soman in anaesthetized rabbits.
abstract: The effect of nimodipine, a vasoactive calcium antagonist, on the disappearance of soman from blood was studied in anaesthetized rabbits intoxicated with soman (10.8 micrograms kg-1 i.v.). Blood samples from the left heart ventricle and femoral artery were used to investigate soman detoxification. The concentrations of the soman isomers C+P- and C-P- in blood samples were determined by gas chromatography coupled with high-resolution mass spectrometry. During the sampling, 15-300 s after soman injection, the soman concentration in control animals decreased from 50 to 0.029 ng mL-1; in animals pre-treated with nimodipine (10 mg kg-1) it decreased from 15 to 0.033 ng mL-1. In animals pre-treated with nimodipine the soman concentration was significantly reduced during the first minute of sampling. No differences were detected between soman concentrations in samples from the heart and femoral artery. Acetylcholinesterase inhibition was also used as an indicator of soman activity; there was no difference between the activity of this enzyme in different peripheral organs of control and nimodipine-treated animals. Nimodipine reduces the initial concentration of soman in the blood, which might be of significance in the treatment of soman intoxication.
authors.affiliation: Defence Research Establishment, Division of NBC Defence, Umeå, Sweden.
authors.forename: B M
authors.initials: BM
authors.lastname: Karlsson
authors.forename: L M
authors.initials: LM
authors.lastname: Waara
authors.forename: S A
authors.initials: SA
authors.lastname: Fredriksson
authors.forename: L O
authors.initials: LO
authors.lastname: Koskinen
mesh_terms: D000110:Acetylcholinesterase / Q000378:metabolism; D000818:Animals; D000931:Antidotes / Q000494:pharmacology*; D001784:Blood Gas Analysis; D002121:Calcium Channel Blockers / Q000494:pharmacology*; D002800:Cholinesterase Inhibitors / Q000097:blood* / Q000493:pharmacokinetics / Q000506:poisoning; D008658:Inactivation, Metabolic; D009553:Nimodipine / Q000494:pharmacology*; D009928:Organ Specificity; D011817:Rabbits; D012999:Soman / Q000097:blood* / Q000493:pharmacokinetics / Q000506:poisoning
chemical_list: D000931:Antidotes; D002121:Calcium Channel Blockers; D002800:Cholinesterase Inhibitors; D009553:Nimodipine; D012999:Soman; D000110:Acetylcholinesterase