[Inhibition of the calcium-sequestering activity of liver microsomes in monobromotrichloromethane poisoning: preliminary studies on possible mechanisms].
The mechanisms by which the in vivo intoxication with BrCCl3 inhibits the calcium sequestration activity of liver microsomes were studied. The initial rate of Ca2+ transport is inhibited by nearly 50% in the intoxicated rats as compared to the controls; this indicates that the active transport of Ca2+ is markedly affected by the intoxication. The microsomal ATPases activities both in the presence and in the absence of Ca2+ were not decreased at all in the intoxicated animals. However, the Ca2+-dependent extra ATP hydrolysis shows a different kinetics in the BrCCl3-poisoned rats with respect to the controls. The release of Ca2+ from Ca2+ loaded liver microsomes is higher in the intoxicated animals. It seems therefore that the increased permeability of the membrane to Ca2+ contributes to some extent to the haloalkane-induced inhibition of the calcium sequestration activity of liver microsomes.
D000251:Adenosine Triphosphatases / Q000378:metabolism; D000818:Animals; D001693:Biological Transport, Active / Q000187:drug effects; D001975:Bromotrichloromethane / Q000633:toxicity*; D002118:Calcium / Q000378:metabolism*; D002463:Cell Membrane Permeability / Q000187:drug effects; D002725:Chloroform / Q000031:analogs & derivatives*; D008862:Microsomes, Liver / Q000187:drug effects / Q000378:metabolism*; D051381:Rats
D002725:Chloroform; D000251:Adenosine Triphosphatases; D001975:Bromotrichloromethane; D002118:Calcium
Inibizione dell'attivita' calcio sequestrante dei microsomi epatici nella intossicazione da monobromotriclorometano: studi preliminari sui possibili meccanismi.