valinomycin and dodecyl-sulfate

valinomycin has been researched along with dodecyl-sulfate* in 1 studies

Other Studies

1 other study(ies) available for valinomycin and dodecyl-sulfate

Article	Year
Activation of ion-conducting pathways in the inner mitochondrial membrane - an unrecognized activity of fatty acid? FEBS letters, 2001, Feb-23, Volume: 491, Issue:1-2 The effect of non-esterified myristate (C14:0) or dodecyl sulfate was studied on passive swelling of rat liver mitochondria suspended in hypotonic alkaline KCl medium in the absence of the potassium ionophore valinomycin. Both compounds rapidly initiated large-amplitude swelling. However, they failed to initiate swelling when the mitochondria were suspended in hypotonic alkaline sucrose medium. In contrast to myristate or dodecyl sulfate, the non-ionic detergent Triton X-100 initiated swelling of mitochondria in both of the media. The following findings indicate that the inner mitochondrial membrane (IMM) is permeabilized by myristate to K+ and Cl- in a specific manner. (i) Swelling initiated by myristate did not respond to cyclosporin A, (ii) the protonophoric uncoupler FCCP was unable to mimic the myristate effect on swelling, and (iii) myristate-induced Cl- -permeation (measured with KCl medium plus valinomycin) was inhibited by N,N'-dicyclohexylcarbodiimide, quinine or ATP. Myristate- or dodecyl sulfate-initiated swelling was paralleled by the lowering of endogenous Mg2+ content. Both effects, stimulation of swelling and depletion of endogenous Mg2+ are correlated with each other. Similar effects have been reported previously for the carboxylic divalent cation ionophore calcimycin (A23187). The A23187-induced swelling has identical inhibiting characteristics on Cl- -permeation with respect to N,N'-dicyclohexylcarbodiimide, quinine and ATP as the myristate-stimulated swelling. Therefore, we conclude that non-esterified fatty acids increase the permeability of mitochondria to K+ and Cl- at alkaline pH by activating Mg2+-dependent ion-conducting pathways in IMM. Topics: Animals; Calcimycin; Cell Membrane Permeability; Detergents; Fatty Acids, Nonesterified; Female; Hydrogen-Ion Concentration; In Vitro Techniques; Intracellular Membranes; Ionophores; Magnesium; Mitochondria, Liver; Mitochondrial Swelling; Myristates; Octoxynol; Potassium Chloride; Rats; Rats, Wistar; Sodium Dodecyl Sulfate; Surface-Active Agents; Valinomycin	2001

Article

Year

Activation of ion-conducting pathways in the inner mitochondrial membrane - an unrecognized activity of fatty acid?

FEBS letters, 2001, Feb-23, Volume: 491, Issue:1-2

The effect of non-esterified myristate (C14:0) or dodecyl sulfate was studied on passive swelling of rat liver mitochondria suspended in hypotonic alkaline KCl medium in the absence of the potassium ionophore valinomycin. Both compounds rapidly initiated large-amplitude swelling. However, they failed to initiate swelling when the mitochondria were suspended in hypotonic alkaline sucrose medium. In contrast to myristate or dodecyl sulfate, the non-ionic detergent Triton X-100 initiated swelling of mitochondria in both of the media. The following findings indicate that the inner mitochondrial membrane (IMM) is permeabilized by myristate to K+ and Cl- in a specific manner. (i) Swelling initiated by myristate did not respond to cyclosporin A, (ii) the protonophoric uncoupler FCCP was unable to mimic the myristate effect on swelling, and (iii) myristate-induced Cl- -permeation (measured with KCl medium plus valinomycin) was inhibited by N,N'-dicyclohexylcarbodiimide, quinine or ATP. Myristate- or dodecyl sulfate-initiated swelling was paralleled by the lowering of endogenous Mg2+ content. Both effects, stimulation of swelling and depletion of endogenous Mg2+ are correlated with each other. Similar effects have been reported previously for the carboxylic divalent cation ionophore calcimycin (A23187). The A23187-induced swelling has identical inhibiting characteristics on Cl- -permeation with respect to N,N'-dicyclohexylcarbodiimide, quinine and ATP as the myristate-stimulated swelling. Therefore, we conclude that non-esterified fatty acids increase the permeability of mitochondria to K+ and Cl- at alkaline pH by activating Mg2+-dependent ion-conducting pathways in IMM.

Topics: Animals; Calcimycin; Cell Membrane Permeability; Detergents; Fatty Acids, Nonesterified; Female; Hydrogen-Ion Concentration; In Vitro Techniques; Intracellular Membranes; Ionophores; Magnesium; Mitochondria, Liver; Mitochondrial Swelling; Myristates; Octoxynol; Potassium Chloride; Rats; Rats, Wistar; Sodium Dodecyl Sulfate; Surface-Active Agents; Valinomycin

2001