Cardiotoxic actions of doxepin and barium chloride in conscious rabbits.
Infusion of doxepin (Dx) i.v. to conscious rabbits induced dose dependently cardiac dysrhythmias of varying severity. Attempts to reduce sympathetic tone with diazepam or clonidine failed to modify Dx effects. Activation of the heart with aminophylline sensitized the animals to Dx effects. Infusion of barium chloride (Ba) caused severe ventricular dysrhythmias which were promptly abolished or reduced by verapamil. A subtoxic dose of Dx, but not diazepam, clonidine or taurine, counteracted Ba effects. Both the toxic and "therapeutic" effects of Dx might depend on its "quinidine-like" membrane effects.
Mattila
M J
MJ
Anyos
K
K
Puisto
E L
EL
D000818:Animals; D001145:Arrhythmias, Cardiac / Q000139:chemically induced; D001464:Barium / Q000633:toxicity*; D017609:Barium Compounds; D002712:Chlorides; D004316:Doxepin / Q000633:toxicity*; D005260:Female; D006321:Heart / Q000187:drug effects*; D006339:Heart Rate / Q000187:drug effects; D008297:Male; D011817:Rabbits; D013654:Taurine / Q000494:pharmacology; D014700:Verapamil / Q000494:pharmacology
D017609:Barium Compounds; D002712:Chlorides; C024986:barium chloride; D004316:Doxepin; D013654:Taurine; D001464:Barium; D014700:Verapamil