Relationship between nonspecific airway hyperreactivity and antigen-induced contraction in an allergic animal model...

Tracheal strips from actively sensitized guinea pigs exhibited an enhanced responsiveness (greater maximal effects; Emax) and sensitivity (smaller effective concentration 50%; pD2) to CaCl2 (in K(+)-depolarized tissues), KCl and histamine compared with that of strips from nonsensitized animals. A significant correlation was found between the magnitude of the contraction produced by bovine serum albumin (1 mg/ml) and the Emax and pD2 values of CaCl2, KCl and histamine in tracheal strips from sensitized guinea pigs. This indicates that specific and nonspecific challenges correlate in sensitized guinea pig trachea.