ovalbumin and sulfuric-acid

Tachykinins are involved in the development of bronchial inflammation and airway hyperresponsiveness (AHR); however, the role of the neurokinin-1 (NK(1)) receptor in acid-aerosol-induced bronchial impairment in asthmatic patients remains controversial.. To investigate the effects on the NK(1) receptor antagonist FK888 the neurokinin-2 (NK(2)) receptor antagonist SR48968 on sulfuric-acid (H(2)SO(4))-induced AHR in guinea pigs, specific airways resistance (sRaw) and airways responsiveness to methacholine (MCh) were measured before and after 6 h of exposure to H(2)SO(4) aerosol (pH 1.7, 82 mg/m(3)) in ovalbumin-sensitized guinea pigs.. Airway responsiveness to MCh significantly increased (p<0. 05) after the exposure, however sRaw did not. Treatment with FK888 significantly inhibited (p<0.05) H(2)SO(4)-induced AHR in a dose-dependent manner, as did SR48968.. These results suggest that not only NK(2) but also NK(1) receptors might have important roles in the development of acid-aerosol-induced AHR.

Topics: Aerosols; Airway Resistance; Animals; Benzamides; Bronchial Hyperreactivity; Bronchial Provocation Tests; Bronchoconstriction; Dipeptides; Guinea Pigs; Indoles; Male; Methacholine Chloride; Nebulizers and Vaporizers; Neurokinin-1 Receptor Antagonists; Ovalbumin; Piperidines; Receptors, Neurokinin-2; Sulfuric Acids