Abnormal mucociliary transport in allergic patients with antigen-induced bronchospasm: role of slow reacting substance of anaphylaxis.
We evaluated the possible role of slow reacting substance of anaphylaxis (SRS-A) in mediating mucociliary dysfunction in allergic asthma. In 6 asymptomatic nonsmokers with ragweed asthma, we measured specific airway conductance (SGaw) and tracheal mucous velocity (TMV) before and after bronchial challenge with ragweed extract, with or without pretreatment with 0.5% and 1% FPL-55712 (SRS-A antagonist). Mean baseline TMV was 8.9 mm/min (SD, 1.1). Placebo and FPL-55712 per se had no effect on TMV. With placebo pretreatment, the doses of ragweed extract that resulted in a decrease in SGaw by more than 35% from baseline, led to an immediate decrease in TMV to 74% of baseline (p less than 0.05), returning to baseline within 2 h. With 0.5% and 1% FPL-55712 pretreatment, doses of ragweed extract that resulted in a similar decrease in SGaw led to an increase in TMV to 130% and 126% of baseline (p less than 0.05), respectively, immediately after antigen challenge and returned to baseline 2 h postchallenge. Inhalation of 1% FPL-55712 immediately after antigen challenge prevented the decrease in TMV. These results indicate that (a) SRS-A liberated during airway anaphylaxis impairs mucous transport, and (b) the antigen-induced increase in TMV after pretreatment with an  SRS-A antagonist may reflect a stimulatory effect of other chemical mediators of anaphylaxis.
D000293:Adolescent; D000328:Adult; D000403:Airway Resistance; D001249:Asthma / Q000503:physiopathology*; D001985:Bronchial Provocation Tests / Q000379:methods*; D001986:Bronchial Spasm / Q000503:physiopathology*; D002867:Chromones / Q000627:therapeutic use; D002923:Cilia / Q000502:physiology; D004987:Ethers / Q000627:therapeutic use; D005260:Female; D005652:Functional Residual Capacity; D006801:Humans; D008297:Male; D008875:Middle Aged; D009093:Mucus / Q000502:physiology*; D012129:Respiratory Function Tests; D013189:SRS-A / Q000502:physiology*; D014132:Trachea / Q000503:physiopathology
D002867:Chromones; D004987:Ethers; D013189:SRS-A; C006312:FPL 55712