title: [A study of passive Ca2+ flow through the sarcoplasmic reticulum of skeletal muscles. I. Passive Ca2+ efflux from vesicle membranes].
abstract: The same level of passively loaded Ca2+ was observed both in the heavy (enriched in terminal cisternae) and light (enriched in longitudinal reticulum) sarcoplasmic reticulum (SR) fractions. The level of passively loaded Ca2+ of the both SR fractions decreased in the presence of 150 mM K+. However the rate and extent of Ca2+ release was greater from heavy SR fraction. The rate of Ca2+ release under conditions of antiport of K+, Na+, choline+ and gluconate-, Cl-, SCH- increased proportion with their permeability through the SR membrane. The initial rate of Ca2+ release also became higher under equal concentration of monovalent cation chloride both inside and outside the SR vesicles. Apparently, in this case Ca2+ release occurs through Ca-channels which are open at a membrane potential.
authors.forename: V A
authors.initials: VA
authors.lastname: Tugaĭ
authors.forename: G P
authors.initials: GP
authors.lastname: Diadiusha
authors.forename: A N
authors.initials: AN
authors.lastname: Zakharchenko
authors.forename: N N
authors.initials: NN
authors.lastname: Zemlianaia
mesh_terms: D000818:Animals; D001692:Biological Transport; D002118:Calcium / Q000378:metabolism*; D002352:Carrier Proteins / Q000378:metabolism; D009132:Muscles / Q000378:metabolism*; D011188:Potassium / Q000378:metabolism; D012519:Sarcoplasmic Reticulum / Q000378:metabolism*; D012964:Sodium / Q000378:metabolism; D028021:Sodium-Potassium-Chloride Symporters
chemical_list: D002352:Carrier Proteins; D028021:Sodium-Potassium-Chloride Symporters; D012964:Sodium; D011188:Potassium; D002118:Calcium
vernacular_title: Issledovanie passivnykh potokov Ca2+ cherez membranu sarkoplazmaticheskogo retikuluma skeletnykh myshts. I. Passivnyĭ vykhod Ca2+ iz membrannykh vezikul.