Cocaine increases intracellular calcium in the interferon-gamma-primed macrophages but not in the LPS-primed-macrophages.
Calcium is required for antigen presentation. In the past study, we found that cocaine increased macrophage antigen-presenting activity. To investigate whether cocaine induces a calcium influx into macrophage cytosol, we used Fura2-AM to directly test the macrophage intracellular calcium concentration [Ca2+]i under the influence of different concentrations of cocaine after macrophages were primed by IFN-gamma or LPS. We report here that cocaine increases the IFN-gamma-primed macrophage [Ca2+]i, but it does not affect the LPS-primed macrophage [Ca2+]i. Furthermore, calcium blocker, nifedipine, blocks the effect of cocaine, suggesting that extracellular calcium enters the cytosol through the L-channel.
Shen
H M
HM
Department of Pathology, College of Medicine, University of Illinois at Chicago, Chicago, IL 60612, USA.
Dudeja
P K
PK
Anderson
K
K
Ou
D W
DW
D000818:Animals; D000938:Antigen-Presenting Cells / Q000187:drug effects; D002118:Calcium / Q000378:metabolism*; D002121:Calcium Channel Blockers / Q000494:pharmacology; D003042:Cocaine / Q000037:antagonists & inhibitors / Q000494:pharmacology*; D005456:Fluorescent Dyes; D016257:Fura-2; D066298:In Vitro Techniques; D007371:Interferon-gamma / Q000494:pharmacology*; D008070:Lipopolysaccharides / Q000494:pharmacology*; D008264:Macrophages / Q000187:drug effects / Q000378:metabolism*; D051379:Mice; D008807:Mice, Inbred BALB C; D009543:Nifedipine / Q000494:pharmacology
D002121:Calcium Channel Blockers; D005456:Fluorescent Dyes; D008070:Lipopolysaccharides; D007371:Interferon-gamma; D003042:Cocaine; D009543:Nifedipine; D002118:Calcium; D016257:Fura-2