[Effective diameter of pores in rat liver mitochondria inner membrane and selectivity of transport of monovalent cations with a submicromolar concentration of Ca2+ ions or A23187 and EDTA].
Studies of swelling of rat liver mitochondria in isoosmotic solutions of nonelectrolytes in the presence of respiration inhibitors revealed that submicromolar concentrations of Ca2+ increase the diameter of pores in the inner mitochondrial membrane--from 5.5-6.0 A (10(-8) M Ca2+) up to 7.5 A (3 x 10(-7) M Ca2+) and 8.0-8.5 A (6 x 10(-7) M Ca2+); these increases are prevented by cyclosporin A. The inner mitochondrial membrane with an effective pore diameter of 7.5 A is readily permeable for potassium but not for sodium ions, although with an increase in the effective pore diameter up to 8.0-8.5 A the selectivity of the K(+)-Na+ channel decreases. A conclusion is drawn that in the presence of submicromolar concentrations of Ca2+ the conductivity of the cyclosporin-sensitive pore for monovalent cations increases in the following order: K > Na > Li.
Gaĭnutdinov
M Kh
MKh
Konov
V V
VV
Ishmukhamedov
R N
RN
Zakharova
T N
TN
Khalilova
M A
MA
Safarov
K S
KS
D000818:Animals; D001692:Biological Transport; D000001:Calcimycin / Q000494:pharmacology*; D002118:Calcium / Q000494:pharmacology*; D002413:Cations, Divalent; D002414:Cations, Monovalent; D004492:Edetic Acid / Q000494:pharmacology*; D007425:Intracellular Membranes / Q000378:metabolism*; D008094:Lithium / Q000378:metabolism; D008297:Male; D008930:Mitochondria, Liver / Q000378:metabolism*; D008933:Mitochondrial Swelling; D009994:Osmolar Concentration; D011188:Potassium / Q000378:metabolism; D051381:Rats; D012964:Sodium / Q000378:metabolism
D002413:Cations, Divalent; D002414:Cations, Monovalent; D000001:Calcimycin; D008094:Lithium; D004492:Edetic Acid; D012964:Sodium; D011188:Potassium; D002118:Calcium
Effektivnyĭ diameter pory vo vnutrenneĭ membrane mitokhondriĭ pecheni krysy i selektivnost' transporta odnovalentnykh kationov pri deĭstvii submikromoliarnykh kontsentratsiĭ ionov Ca2+ ili A23187 i EDTA.