[The effect of Cd2+ on the respiration and swelling of isolated rat liver mitochondria in incubation media of different compositions].
We studied a change in Cd2+ influence on state 4 and 3 respiration and on 2,4-dinitrophenol (DNP)-stimulated respiration of isolated rat liver mitochondria, after replacement of KCl for equimolar quantities of NaCl, LiCl or for 200 mM sucrose in the incubation medium. Cd2+ concentrations higher than 2.5 microM reduced state 3 respiration or DNP-stimulated one in KCl medium (control), and activated state 4 respiration, however, at Cd2+ concentrations higher than 12.5 microM the respiratory activation became short-term with a following reduction in respiration. Cd2+ influence on respiration of mitochondria increased in the medium with NaCl, which resulted in decreasing the acting Cd2+ concentrations and in activating state 4 respiration more intensely. Cd2+ did not modify respiration of mitochondria in the experiments with LiCl in the medium, except that Cd2+ in concentrations higher than 10 microM decreased the state 4 respiration mitochondria just as in NaCl experiments. On the contrary, Cd2+ influence on respiration of mitochondria was seen decreased in the medium with sucrose. This was displayed in the increase in Cd2+ acting concentrations and in the decrease in activation of state 4 respiration mitochondria, and is associated with the nonosmotic character of these effects. On 20 microM Cd2+ concentration only, an extensive swelling of nonenergized mitochondria was observed in 12.5 mM nitrate media and its increase in series of Li < Na < K < NH4. The initially low swelling of succinate energized mitochondria in KCl medium was increased at raising Cd2+ concentration in this medium. A non-uniform Cd2+ influence on respiration and mitochondrial swelling in the above incubated media may be firstly associated with different effects of K+, Na+, Li+ and sucrose on membrane ion permeability and on Cd+ binding with the membrane, and, secondly, correlated with the action of medium components on energy dependent Cd2+ uptake by mitochondria and on Cd2+ penetration to mitochondrial respiratory enzymes.
Korotkov
S M
SM
Skul'skiĭ
I A
IA
D019297:2,4-Dinitrophenol / Q000494:pharmacology; D000818:Animals; D002104:Cadmium / Q000494:pharmacology*; D002458:Cell Fractionation; D019069:Cell Respiration / Q000187:drug effects / Q000502:physiology; D003470:Culture Media; D004305:Dose-Response Relationship, Drug; D066298:In Vitro Techniques; D007425:Intracellular Membranes / Q000187:drug effects / Q000502:physiology; D008297:Male; D008930:Mitochondria, Liver / Q000187:drug effects* / Q000378:metabolism; D008933:Mitochondrial Swelling / Q000187:drug effects* / Q000502:physiology; D010539:Permeability / Q000187:drug effects; D051381:Rats; D013053:Spectrophotometry; D014475:Uncoupling Agents / Q000494:pharmacology
D003470:Culture Media; D014475:Uncoupling Agents; D002104:Cadmium; D019297:2,4-Dinitrophenol
Vliianie Cd2+ na dykhanie i nabukhanie izolirovannykh mitokhondriĭ pecheni krysy v inkubatsionnykh sredakh raznogo sostava.