title: On the mechanisms of the inhibition of calcium sequestering activity of liver microsomes in bromotrichloromethane intoxication.
abstract: 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 ATPase 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.
mesh_terms: D000255:Adenosine Triphosphate / Q000378:metabolism; D000818:Animals; D001975:Bromotrichloromethane / Q000506:poisoning*; D002118:Calcium / Q000378:metabolism*; D000252:Calcium-Transporting ATPases / Q000378:metabolism; D002725:Chloroform / Q000031:analogs & derivatives*; D004734:Energy Metabolism; D007700:Kinetics; D008297:Male; D008862:Microsomes, Liver / Q000187:drug effects / Q000378:metabolism*; D010070:Oxalates / Q000494:pharmacology; D019815:Oxalic Acid; D011506:Proteins / Q000378:metabolism; D051381:Rats; D011919:Rats, Inbred Strains
chemical_list: D010070:Oxalates; D011506:Proteins; D002725:Chloroform; D000255:Adenosine Triphosphate; D019815:Oxalic Acid; D000252:Calcium-Transporting ATPases; D001975:Bromotrichloromethane; D002118:Calcium