Release of histamine from skin during in vitro anaphylaxis. Cutaneous anaphylaxis in vitro

Studies on histamine secretion from enzymically dispersed cutaneous mast cells of the rat

A method has been developed for the enzymic dissociation of rat skin into its component cells. The resulting suspensions contained 3-5% mast cells. The latter were intact as judged by light microscopy and exhibited a low spontaneous release of histamine. Cells obtained from actively sensitized animals released histamine on challenge with specific antigen. The process was rapid, being essentially complete within 1 min, and was both calcium-and temperature-dependent. The cells also responded to antirat IgE and to calcium ionophores but showed a selective, time-dependent reactivity toward defined chemical histamine liberators. On the basis of these results the properties of the cutaneous mast cell are compared with those previously reported for mastocytes from other sources and discussed in terms of the general heterogeneity of this cell population.

Treatment of atopic eczema in children: clinical trial of 10% sodium cromoglycate ointment

In a double-blind randomised group-comparative trial 21 children with chronic atopic eczema were treated twice daily for up to 12 weeks with an ointment containing 10% sodium cromoglycate (SCG) in white soft paraffin. A similar group of 21 children was treated for up to 12 weeks with a placebo ointment consisting of the white soft-paraffin base only. The number of patients who withdrew from the trial because treatment was ineffective was significantly greater in the placebo group (16) than in the SCG group (four). Comparison between the two groups also showed significant improvement in inflammation, lichenification, and cracking and the symptoms of itching and sleep disturbance among those on SCG treatment. At the end of treatment significantly more patients in the SCG group (16) had benefited from treatment compared with only two patients in the placebo group. No patients experienced side effects. I conclude that SCG ointment may be a safe alternative to topical steroids in the treatment of atopic eczema in children.