Submolecular mechanisms underlying in vitro and in vivo effect of cardiac glycosides on contractile activity of myocardial myofibrils during heart failure.
The development of severe heart failure associated with toxicoallergic myocarditis is accompanied by profound structural and conformational changes in the outer domain of actin (major protein in a thin filament of cardiomyocyte sarcomere). These changes were revealed in subdomains 1 (Cys374 and Cys10) and 2 (Lys61 and Tyr69). Structural and conformational changes in the monomer and protomer of the actin thread during heart failure were energetically forbidden. Variations in the distance between amino acid residues exceeded 0.26 nm. They were partly or completely reversible in vivo under the influence of cardiotropic drug refracterin with high antihypoxic activity, as well as in vitro after treatment with digitalis preparations optimizing the concentration of ATP.
Sukoyan
G V
GV
N. V. Karsanov Republican Research Center for Medical Biophysics and Implementation of New Biomedical Technologies, Tbilisi. galinasukoian@mail.ru
Berberashvili
T M
TM
Karsanov
N V
NV
D000113:Acetyldigoxins / Q000494:pharmacology; D000818:Animals; D002301:Cardiac Glycosides / Q000737:chemistry*; D006331:Heart Diseases / Q000378:metabolism / Q000473:pathology*; D066298:In Vitro Techniques; D008968:Molecular Conformation; D009119:Muscle Contraction; D009132:Muscles / Q000473:pathology*; D009200:Myocardial Contraction; D017202:Myocardial Ischemia / Q000473:pathology; D009205:Myocarditis / Q000473:pathology; D009210:Myofibrils / Q000378:metabolism / Q000473:pathology*; D011817:Rabbits
D000113:Acetyldigoxins; D002301:Cardiac Glycosides