[Changes in the electric activity of the myocardial fibers of the guinea pig during local anaphylactic reactions under conditions of inactivation of "rapid" sodium channels].
Changes of electrical activity (intracellular records) of guinea pig heart auriculus were studied during experimental cardiac anaphylaxis (ovalbumine being used as an antigen). Fast Na channels of the myocardial fibers having been depressed by long-standing depolarization in K+-rich (20 mM) Tyrode solutions, only the low-amplitude slow responses to brief stimuli were recorded. Addition of ovalbumine (2.10(-4) g/ml), histamine (1.10(-4) g/ml) or adrenaline (5.10(-6) g/ml) to the K-rich solution led to increase of both the amplitude and the duration of the responses. These data supported the hypothesis on the principal role of slow Na--Ca channels in the mechanism of the changes in the electrical activity of the myocardial fibers during cardiac anaphylaxis.
D000707:Anaphylaxis / Q000378:metabolism / Q000503:physiopathology*; D000818:Animals; D004594:Electrophysiology; D004837:Epinephrine / Q000494:pharmacology; D006168:Guinea Pigs; D006321:Heart / Q000187:drug effects / Q000503:physiopathology*; D006632:Histamine / Q000494:pharmacology; D009206:Myocardium / Q000378:metabolism*; D009431:Neural Conduction; D010047:Ovalbumin; D012964:Sodium / Q000378:metabolism*
D006632:Histamine; D010047:Ovalbumin; D012964:Sodium; D004837:Epinephrine
Izmeneniia élektricheskoĭ aktivnosti miokardial'nykh volokon morskoĭ svinki pri mestnoĭ anafilakticheskoĭ reaktsii v usloviiakh intaktivatsii "bystrykh" natrievykh kanalov