抗原誘発後の鼻粘膜ＳＲＳ‐Ａ含有量の経時的変化

Abstract

We evaluated the time course of production of SRS-A in the nasal mucosa after antigen challenge in the guinea pigs with nasal allergy and the effect of Ketotifen sprayed topically over the nasal mucosa on SRS-A production. Fifty-six Hartley strain guinea pigs were sensitized passively by intravenous injection of 0.4 ml of sera containing antiovaTbumin IgE and γ1 antibody (7 days' PCA titer, ×1664; 48 hours' RCA titer, ×5632). After 7 days, all animals received nasal challenge with 50 μl×2 of 1 % ovalbumin. Thirty-two animals were subdivided into 8 groups that were killed before the challenge and 15 min, 30 min, 1 hr, 3 hr and 12 hr after antigen challenge. The nasal mucosa was removed and the amount of LTC4, LTD4 and LTE4 in the nasal mucosa was measured using high-powered liquid chromatography combined with radioimmunoassay. In 12 animals, nasal spray of 0.1 mg Ketotifen dissolved in normal saline was given once a day for 6 days until the day of antigen challenge and another 12 animals were given nasal spray of normal saline as a control. Thirty minutes after nasal antigen challenge, the animals were killed and the nasal mucosa was removed to measure the amount of SRS-A. LTC4, LTD4 and LTE4 in the nasal mucosa increased significantly between 15 and 60 min after antigen challenge and then decreased markedly. Ketotifen sprayed topically over the nasal mucosa significantly inhibited production of LTC4, LTD4 and LTE4 by as much as 50%.