Cutaneous and basophilic sensitivity to substance P and gastrin in non-atopic versus atopic subjects

We compared the Cutaneous reaction to intradermal injection of substance P, gastrin and histamine in asymptomatic atopic subjects with a history of hay fever and/or asthma versus non-atopk healthy volunteers. We also studied in these two groups the basophilic histamine release induced by substance P and gastrin with that obtained with anti-human IgE and Con A. Intradermal injection of substance P (3–300 pM) and gastrin (3–30 pM) caused a wheal and flare reaction which was comparable in both groups of subjects. Substance P 10⁻⁴M caused a mean basophilic histamine release of about 15% in atopic and non-atopic Subjects. Gastrin was not effective in this model. Anti-IgE and Con A-induced histamine release was significantly higher in atopic than in non-atopic volunteers.