The role of leukotrienes B4 (LTB4) and C4 (LTC4) in pathophysiology of asthma in the elderly. Relationship to bronchial hyperresponsiveness and FEV1.O%

The generation of leukotrienes B4 (LTB4) and C4 (LTC4) by leucocytes stimulated with Ca ionophore A23187 was examined in 67 patients with asthma. 1. The generation of leukotriene B4 (LTB4) by leucocytes was significantly more increased in patients with asthma than in those with pulmonary emphysema (PE) and healthy subjects. The generation of leukotriene C4 (LTC4) was also signficantly more increased in patients with asthma compared to the generation in those with PE and healthy subjects. The generation of both LTB4 and LTC4 was significantly more increased in patients with PE than in healthy subjects. 2. The generation of both LTB4 and LTC4 was larger in patients with asthma over age 70 than in those of other age groups, however, the difference was not significant. 3. The generation of LTC4 was significantly higher in attack stage than in non-attack stage in all age groups of patients with asthma, however, the generation of LTB4 was not significantly different between the two stages. 4. Bronchial hyperresponsiveness to methacholine in patients with asthma tended to decrease with aging, and the bronchial hyperresponsiveness was to a certain extent correlated with the generation of LTB4, but not LTC4. 5. The generation of LTC4 was correlated with value of FEV1.0%. These results may suggest that both LTB4 and LTC4 participate in the pathophysiology of asthma in the elderly.
気管支喘息67例を対象に, Ca ionophoreA23187刺激時の白血球からのロイコトリエンB4(LTB4)およびC4 (LTC4)の産生を観察し,高齢者喘息の臨床病態におけるLTB4,LTC4の役割について検討した｡ 1.LTB4の産生は,気管支喘息において肺気腫および健康人に比べ有意に高い値を示した｡LTC4の産生も同様に気管支喘息において,肺気腫,健康人に比べ有意に高い値30を示した｡LTB4,LTC4いずれの産生も,肺気腫症例において健康人と比べ有意に高い値が観察された。 2.LTB4,LTC4の産生は,70才以上の喘息症例において,他の年齢層の症例に比べより高い値が示されたが,推計学的な有意差は見られなかった｡ 3.高齢者を含めいずれの年齢層の気管支喘息においても,LTC4の産生は発作時に,非発作時に比べ有意の亢進が見られたが,LTB4に関しては発作時,非発作時の間に有意の差は見られなかった｡ 4.気道の過敏性は,年齢が高くなるにつれて低下する傾向が見られた｡そして,この気道の過敏性はLTB4産生とある程度関連していることが示されたが,LTC4との関連は見られなかった｡ 5.FEV1.0%値は,ある程度LTC4産生亢進と関連があることが示された｡ 以上の結果より,70才以上の喘息においても,LTB4,LTC4がその発作時病態に重要な役割を果していることが示唆された｡