Author/Editor		Ferjan, I; Erjavec, F
Title		Micromolar concentrations of EGTA increase histamine secretion from mast cells treated with digitalis glycosides of different polarity
Type		članek
Source		Agents Actions
Vol. and No.		Letnik 38
Publication year		1993
Volume		str. C215-7
Language		eng
Abstract		Histamine release from rat peritoneal mast cells induced by compound 48/80 (1 micro g/ml) after 90 min of preincubation in calcium - free medium is only 8.4 per cent . Cardiotonic glycosides modify the secretion induced by compound 48/80: hydrophilic glycosides potentiate the secretion, and this potentiation decreases with increasing lipophility of the glycosides. Our present study shows that the preincubation (90 min) of mast cells with EGTA (1 micro mol/1) potentiates the histamine release induced by compound 48/80. A further potentiation is found when mast cells are preincubated with EGTA before the addition of digitalis glycosides. The potentiation depends on the polarity ofthe glycoside. Since EGTA influences the secretion only in media containing sodium, the effect of EGTA might be due to its interaction with membcane permeability for Na+ ions. Liposoluble glycosides have an additional intracellular effect, acting on microfilaments and pcoducing a lower or no potentiation of the response.
Descriptors		DIGITALIS GLYCOSIDES HISTAMINE LIBERATION MAST CELLS RATS EGTAZIC ACID SODIUM