title: Release of the membrane-calcium and its relation to the superoxide formation by polymorphonuclear leukocytes.
abstract: The relationship between the intracellular translocation of calcium from the storage pool and the oxidative metabolism was studied. An intracellular calcium-antagonist, TMB-8, inhibited the release of superoxide induced by a calcium ionophore A23187 and the inhibition was relieved by the addition of calcium ions. The release induced by cytochalasin D or by the ingestion of bacteria was similarly inhibited by TMB-8. The mobilization of intracellular divalent cations of leukocytes was monitored by a fluorescent probe, CTC. When the CTC-loaded cells were stimulated with cytochalasin D or E. coli, a fluorescence change ascribable to the release of calcium from the intracellular hydrophobic environment was observed. The dose-response curve of the fluorescence change and that of the superoxide release of th cells were very similar. TMB-8 inhibited both metabolic and fluorescence changes in parallel. The results support the hypothesis that an intracellular translocation of calcium is stimulated the oxidative metabolism of leukocytes.
mesh_terms: D000001:Calcimycin / Q000494:pharmacology; D002118:Calcium / Q000378:metabolism*; D002451:Cell Compartmentation; D002462:Cell Membrane / Q000378:metabolism; D002751:Chlortetracycline; D003572:Cytochalasins / Q000494:pharmacology; D005707:Gallic Acid / Q000031:analogs & derivatives* / Q000494:pharmacology; D009504:Neutrophils / Q000378:metabolism*; D010100:Oxygen / Q000097:blood*; D013050:Spectrometry, Fluorescence; D013481:Superoxides / Q000097:blood*
chemical_list: D003572:Cytochalasins; D013481:Superoxides; D000001:Calcimycin; C006014:8-(N,N-diethylamino)octyl-3,4,5-trimethoxybenzoate; D005707:Gallic Acid; D010100:Oxygen; D002118:Calcium; D002751:Chlortetracycline