Correlation between efficacy of Pranlukast and LTC4 generation by peripheral leukocytes

The correlation between the efficacy of 4-weeks administration with pranlukast, leukotriene receptor antagonist, and LTs generation by peripheral leukocytes were evaluated in 18 patients with mild-persistent asthma. The efficacy of pranlukast administration was assessed by symptom, morning PEF and pulmonary function. Pranlukast were effective in 12/18(67%) patients. In those patients, LTC4 generation before pranlukast administration was significantly high, compared with that in pranlukast-ineffective patients. LTC4 generation decreased after 4-weeks administration with pranlukast in effective patients. In ineffective patients, however, LTC4 generation increased after 4-weeks administration. LTB4 had shown no significant difference between effective and ineffective patients before administration, and LTB4 decreased after 4-weeks in both groups. Proport ion of peripheral eosinophi Is in effective patients were higher than that in ineffective patients, however not significant. After 4-weeks, proportion of eosinophi Is was decreased in effective patients and increased in ineffective patients. These findings suggest that pranlukast is effective for patients with high LTC4 generation and has the effect to suppress the accumulation of eosinophils in such patients.
軽症気管支喘息18例にロイコトリエン受容体桔抗薬プランルカストを4週間投与し，その効果と末梢血白血球からのLTC4，LTB4産生能の関係を検討した．プランルカストの効果は臨床症状，起床時ピークフロー値，肺機能の変化によって判定し，効果群，非効果群の2群に分類した．18例中12例（67％）の症例がプランルカスト投与により，臨床症状の軽減，ピークフロー値の増加，肺機能の改善が認められた．効果群におけるプランルカスト投与前のLTC4値は，非効果群のLTC4値に比較して有意に高値であった．4週間の投与後には 効果群ではLTC4値は減少し，非効果群では増加した．両群のLTB4値はプランルカスト投与前で有意な差は認められず，投与後には両群で減少した．投与前の好酸球分画は，効果群において非効果群に比べ高値であったが，有意な差は認められなかった．4週間の投与後，効果群においては好酸球は減少し，非効果群においては増加した．以上の結果より，プランルカストは末梢血白血球のLTC4産生能が高い症例において効果的であり，好酸球集積を抑制する作用を有すると考えられる．