ISSN:
1420-908X
Keywords:
Intracellular Ca2+
;
Histamine secretion
;
Basophilic leukemia cell
;
Hydroquinone analog
;
Ca2+ ATPase inhibitor
Source:
Springer Online Journal Archives 1860-2000
Topics:
Medicine
Notes:
Abstract The effects of 2,5-di(tert-butyl)-1,4-hydroquinone (DTBHQ) on the intracellular free Ca2+ level ([Ca2+]i) and histamine secretion of rat basophilic leukemia (RBL-2H3) cells were examined. DTBHQ (0.1–10 µmol/l) alone induced rapid and sustained increases in [Ca2+]i in a concentration-dependent manner. In cells sensitized with anti-dinitrophenyl IgE, DTBHQ (10 µmol/1) further increased the antigen (dinitrophenylated BSA)-induced Ca2+ response. In the absence of external Ca2+ with addition of 1 mmol/1 EGTA, both DTBHQ (10 µmol/l) and the antigen (10 µg/ml) induced transient increase in [Ca2+]i. In sensitized cells, both DTBHQ (10 µmol/1) and antigen (10 µg/ml) elicited histamine secretion, although the response was far stronger in the latter case. The DTBHQ-induced histamine secretion was markedly enhanced by addition of the protein kinase C activator, phorbol 12-myristate 13-acetate (TPA) (10 ng/ml) whereas TPA alone did not cause any increase. Moreover, DTBHQ enhanced the antigen-induced histamine secretion. The results suggest that DTBHQ increases [Ca2+]i and enhances antigeninduced histamine secretion while DTBHQ alone does not cause as much histamine secretion as antigen, which support the idea that calcium signals are necessary but are not sufficient for maximum histamine secretion in RBL-2H3 cells.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF01796264
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