[The tissue specificity of the protective action of cytoplasmic factors on the membrane-bound system of Ca2+ transport in the sarcoplasmic reticulum of the heart and the skeletal muscles].
Whether soluble cytoplasmic factors (SCF) can protect the membrane-associated Ca2+ transport system in sarcoplasmic reticulum (SR) was studied in controls, stress and adaptation to it. Ca-transport was damaged in stress much more in the skeletal muscles compared to the heart. Initial performance of Ca-pump in the skeletal muscles was decreased by 43%, in the heart--no change. After stress, thermoresistance of the enzyme in the skeletal muscles was 3-5 times less than in the myocardium. The enzyme reaction on adaptation and stress in both tissues is the same--a significant rise in Ca-pump thermoresistance. When preadapted animals are exposed to stress, deceleration of the initial speed and resistance of the enzyme in the myocardium are fully prevented while in the skeletal muscles Ca-pump resistance is higher than in the controls. In the heart, SCF have a protective effect on thermoresistance. In the skeletal muscles, SCF protect initial speed of the enzyme in the control, in stress and adaptation to it. A cross-over protective SCF (from adapted animals) effect was found on the stress-impaired membrane system of Ca-transport. Adapted SCF elevate 2.5-fold thermoresistance of the enzyme. Correlation between cytoplasmic and membrane protective mechanisms in stress and adaptation to it is considered.
Sazontova
T G
TG
Matskevich
A A
AA
D000208:Acute Disease; D000818:Animals; D001693:Biological Transport, Active / Q000502:physiology; D002118:Calcium / Q000378:metabolism*; D000252:Calcium-Transporting ATPases / Q000378:metabolism; D002462:Cell Membrane / Q000378:metabolism; D003593:Cytoplasm / Q000378:metabolism*; D019610:Cytoprotection / Q000502:physiology*; D008297:Male; D009206:Myocardium / Q000378:metabolism*; D009928:Organ Specificity; D051381:Rats; D017208:Rats, Wistar; D012519:Sarcoplasmic Reticulum / Q000378:metabolism*; D012995:Solubility; D013315:Stress, Psychological / Q000378:metabolism; D013997:Time Factors
D000252:Calcium-Transporting ATPases; D002118:Calcium