[A study on the changes of calcium signal in mast cells activated by antigen].
OBJECTIVE
To study the relationship between the calcium signal and activation of mast cells, laying the foundation for discovering a new potential theraputical target of signal transduction for type I anaphylactic diseases like asthma.


METHODS
The fluorescent Ca2+ indicator Fluo-3 was used to observe and quantitate the calcium signal directly in activated RBL-2H3 mast cells by a flow cytometer and a confocal fluorescence microscope with laser.


RESULTS
Antigens elicited significant increase in intracellular Ca2+ concentration ([Ca2+]i) and histamine release in sensitized cells, maximal [Ca2+]i increase being reached (525 +/- 42) nmol/L (n = 12) within 90-110 s after stimulation. Increase of fluo-3-fluorescence intensity was also observed with the confocal fluorescence microscope in cytosol. No significant increase of [Ca2+]i was observed after addition of EDTA in sensitized cells from an initial value of (79 +/- 3) nmol/L, to (80 +/- 4) nmol/L (P > 0.05, n = 12), but tyrosine phosphorylation was readily observed, and the indirect fluorescent intensity was significantly greater than that in the control group. No significant change of [Ca2+]i was observed with the addition of DNP-BSA after PMA (P > 0.05, n = 8).


CONCLUSIONS
Calcium is involved in the activation process of mast cells stimulated by antigens.
Lu
Y
Y
Department of Respiratory Medicine, Changzheng Hospital, Second Military Medical University, Shanghai 200003, China.
Li
L
L
Luo
W
W
D000814:Aniline Compounds; D000818:Animals; D000941:Antigens / Q000494:pharmacology*; D000001:Calcimycin / Q000494:pharmacology; D002118:Calcium / Q000378:metabolism; D002122:Calcium Chloride / Q000494:pharmacology; D020013:Calcium Signaling / Q000187:drug effects*; D004140:Dinitrophenols / Q000494:pharmacology; D007476:Ionophores / Q000494:pharmacology; D008407:Mast Cells / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism; D018613:Microscopy, Confocal; D008856:Microscopy, Fluorescence; D011493:Protein Kinase C / Q000378:metabolism; D012710:Serum Albumin, Bovine / Q000494:pharmacology; D013997:Time Factors; D014407:Tumor Cells, Cultured; D014966:Xanthenes
D000814:Aniline Compounds; D000941:Antigens; D004140:Dinitrophenols; D007476:Ionophores; D014966:Xanthenes; C034638:dinitrophenyl-bovine serum albumin; C059715:Fluo-3; D012710:Serum Albumin, Bovine; D000001:Calcimycin; D011493:Protein Kinase C; D002122:Calcium Chloride; D002118:Calcium