ISSN:
1420-908X
Keywords:
Key words: RBL-2H3 — Exocytosis — Eclazolast — Calcium — Antiallergic
Source:
Springer Online Journal Archives 1860-2000
Topics:
Medicine
Notes:
Abstract. Objective and Design: In this study, we compared eclazolast with other lipophilic antiallergic drugs, relating to effects on signal transduction pathways, leading to inhibition of exocytosis in a rat basophilic leukemia cell (RBL-2H3). ¶Materials and Methods: Effects of the drugs on mediator release (β-hexosaminidase, arachidonic acid metabolites) after FcεRI activation in RBL-2H3 cell were quantified. Furthermore, effects of the drugs on cellular signalling (Ca2+ influx, intracellular Ca2+ concentration, inositol 1,4,5-trisphosphate (IP3) concentration) were assayed. Effects of the drugs on bilayer and cell membranes have been recorded. ¶Results: It is shown that eclazolast down-regulates IP3 levels. In contrast to lipophilic drugs, eclazolast does not affect artificial bilayers and erythrocyte membranes, and there is no effect on thapsigargin induced Ca2+ influx. The effect of eclazolast was highly dependent on the antigen concentration with which the cells were triggered. ¶Conclusions: The mechanism of action of eclazolast is deviant from lipophilic antiallergic agents. It inhibits exocytosis by intracellularly affecting only direct FcεRI linked processes and not through inhibition of Ca2+ influx channels, as found for membrane disturbing lipophilic drugs.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/s000110050505
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