Experimental porcine malignant hyperthermia: the activity of certain transporting enzymes and myofibrillar calcium-binding protein content in the muscle fibre.
The activity of enzymes transporting calcium across the membrane of the muscle fibre and sarcoplasmic reticulum was studied. The activity of actomyosin Mg2+-ATPase and the composition of troponin were investigated also. In seven Pietrain pigs halothane alone or with suxamethonium induced the malignant hyperthermia syndrome. In the animals with malignant hyperthermia Ca2+-ATPase was not activated in the plasma membranes of the muscle fibres, when compared with control animals (n = 4). An increase of Ca2+-ATPase of the sarcoplasmic reticulum was observed in animals with malignant hyperthermia; the opposite was noted in the control group. No significant changes in the activity of Mg2+-ATPase of the sarcoplasmic reticulum and of Mg2+-ATPase of actomyosin were observed after exposure to halothane in control pigs and those with malignant hyperthermia. The amount of troponin C was significantly changed in the animals with malignant hyperthermia. The mechanism of the development of malignant hyperthermia syndrome is discussed.
D000205:Actomyosin / Q000378:metabolism; D000251:Adenosine Triphosphatases / Q000378:metabolism; D000818:Animals; D017301:Ca(2+) Mg(2+)-ATPase; D000252:Calcium-Transporting ATPases / Q000378:metabolism*; D002462:Cell Membrane / Q000201:enzymology; D008305:Malignant Hyperthermia / Q000378:metabolism*; D009132:Muscles / Q000378:metabolism*; D012519:Sarcoplasmic Reticulum / Q000201:enzymology; D013552:Swine; D014336:Troponin / Q000378:metabolism
D014336:Troponin; D000205:Actomyosin; D000251:Adenosine Triphosphatases; D017301:Ca(2+) Mg(2+)-ATPase; D000252:Calcium-Transporting ATPases