[Changes in the ATP-ase activity of skeletal muscle nuclei of rabbits with dystrophy and following their delipidation]. / Zminy ATF-aznoï aktyvnosti iader skeletnykh m'iaziv kroliv za dystrofiï ta pislia ïkh delipiduvannia

The level of the ATPase activity in the skeletal muscles nuclei with experimental muscular dystrophy and the sensitivity to bivalent (Mg2+, Ca2+) and univalent (Na+, K+) cations under conditions of delipidation were studied. It is established that among ATPases of the young rabbit skeletal muscles nuclei there is ATPase sensitive to monovalent cations: the presence of Na+ or K+ produces a 45% increase in its activity in some experiments as compared to the initial level. This activation is attributed to Mg2+, Ca2+-ATPase the action of which is not realized in the presence of EGTA-chelator of calcium ions. A decrease in the total ATPase activity in the skeletal muscles nuclei resulted from the experimental muscular dystrophy development occurs due to a decrease in the Mg2+, Ca2+-ATPase activity as the ability for activation by the monovalent cations is practically lost under these conditions. Delipidation of the skeletal muscles nuclei, which results in their loss of some phospholipids and cholesterin, is accompanied by the ATPase activity decrease. At the same time the nuclei ATPase activity lose its ability to activate by monovalent cations: Na+, K+. A conclusion is made that during delipidation the decrease in the total ATPase activity is due to a decrease in the activity of its Mg2+, Ca2+-part.

[Lipid levels in rabbit sarcolemma normally and during experimental muscular dystrophy]. / Vmist lipidiv u sarkolemi kroliv u normi ta za eksperymental'noï m'iazovoï distrofiï

The cholesterin content, total content and phsopholipid composition were studied in sarcolemma of normal rabbits and those with experimental muscular dystrophy. The total content of phospholipids in the sarcolemma of young normal rabbits is 4.8 mg of phosphorus per 1 mg of protein which is higher than that in the sarcolemma of adult rabbits 33%. With experimental muscular dystrophy the content of cholesterin is 2.7 as high as its content in the sarcolemma of the normal rabbits. It is established that the content of phosphatidilserine in the sarcolemma of young normal rabbits is by 61% higher than that in adult animals. The content of phosphatidilserine of lysophosphatidilcholine decreases by 40 and 39%, respectively, with dystrophy. The content of phosphatidilcholine increases by 16% as compared with sarcolemma extracted from the muscles of the young normal rabbits. Molar ratio of phospholipid/cholesterine in the sarcolemma of normal rabbits is 1.8 and decreases with the experimental muscular dystrophy to 0.75.