Inhibition by disodium cromoglycate of anaphylactic histamine secretion from rat peritoneal mast cells in the presence of phosphatidylserine

Mucosal damage during intestinal anaphylaxis in the rat. Effect of betamethasone and disodium cromoglycate

In this study, two antiallergic compounds, betamethasone and disodium cromoglycate were tested in an animal model of intestinal anaphylaxis. Rats, immunized with Nippostrongylus brasiliensis, were challenged intravenously with whole worm antigen or saline. Antigen challenge resulted in significant abnormalities: epithelial damage with shorter villi, decreased activity of digestive enzymes, decreased levels of mucosal histamine, a mast cell mediator, and increased blood uptake of [51Cr]EDTA from the lumen. Low-dose betamethasone, 24 and 48 hr before antigen, was not effective in preventing the effects: villus damage and increased [51Cr]EDTA uptake were seen, although mucosal mast cell numbers were significantly reduced by the drug. High-dose betamethasone completely prevented intestinal anaphylaxis: villus height, digestive function, and [51Cr]EDTA recovery in antigen-challenged animals were not significantly different from controls. Mucosal histamine levels and mast cells were significantly reduced in the high dose betamethasone group. Oral disodium cromoglycate did not prevent the abnormalities but provided a slight beneficial effect.

Auranofin inhibits histamine release from rat peritoneal mast cells

The effect of auranofin on histamine release from immunologic and non-immunologic activated rat peritoneal mast cells cocultured with 3T3 fibroblasts (MC/3T3) was investigated. When MC/3T3 were preincubated with 2 x 10(-5) M auranofin and thereafter challenged with anti-IgE antibodies, a maximal inhibition of histamine release (86.2%) was obtained. Non-immunological histamine release induced by compound 48/80, substance P and bradykinin was inhibited to a lesser degree, i.e. 36.0%, 37.6% and 24.0% respectively. Simultaneous incubation of auranofin and the stimulating agents resulted in a higher inhibition of histamine release: anti-IgE antibodies--92.0%; compound 48/80--73.5%; substance P--46.1%. We conclude that auranofin effectively reduces histamine release from immunologic and non-immunologic activated mast cells. This may be relevant to the control of allergic reactions.

Effects of sodium cromoglycate and nedocromil sodium on histamine secretion from human lung mast cells

Sodium cromoglycate and nedocromil sodium produced a dose dependent inhibition of histamine secretion from human pulmonary mast cells obtained by bronchoalveolar lavage and by enzymatic dissociation of lung parenchyma. Both compounds were significantly more active against the lavage cells than against the dispersed lung cells, and nedocromil sodium was an order of magnitude more effective than sodium cromoglycate against both cell types. Tachyphylaxis was observed with the parenchymal cells but not with the lavage cells. Nedocromil sodium and sodium cromoglycate also inhibited histamine release from the lavage cells of patients with sarcoidosis and extrinsic asthma.

On the mechanism of dextran-induced histamine secretion from rat peritoneal mast cells

The mechanism of histamine release induced from isolated rat peritoneal mast cells by clinical dextran was examined in detail. The putative involvement of cell-fixed IgE antibodies in the process was discounted by a number of experimental approaches. Instead, the characteristics of the release were found to be consistent with the interaction of the polysaccharide with specific glucoreceptors on the mast cell membrane.

Some studies on the release of histamine from mast cells treated with polymyxin

Polymyxin B produced a dose-dependent release of histamine from rat peritoneal mast cells. The response was non-cytotoxic and extremely rapid. The release was maximal in the presence of extracellular calcium ions but a substantial component persisted in the absence of the cation. This component was virtually abolished by pretreatment with the ionophore A23187 in the presence of a chelating agent and thus probably reflected the mobilization of intracellular stores of calcium. Hamster peritoneal cells also responded to polymyxin but were less reactive than those of the rat. Mouse peritoneal cells and guinea-pig lung mast cells responded only at very high concentrations. These results further emphasize the functional heterogeneity of mast cells from different sources. Histamine release from rat peritoneal mast cells was inhibited in dose-dependent fashion by cAMP analogues and anti-allergic drugs. The inhibitory effect varied inversely with the magnitude of the control secretion. With the exception of disodium cromoglycate, the test drugs were essentially equiactive in the presence and absence of extracellular calcium. These results are discussed in terms of the possible mode of action of these compounds.