Effect of acetylcholinesterase activity on pathogenesis of airway hyperresponsiveness in guinea pigs.

To clarify the effect of acetylcholinesterase (AChE) on the pathogenesis of airway hyperresponsiveness, AChE activities in tracheal smooth muscle and lung tissue from congenitally bronchial-hypersensitive (BHS) and bronchial-hyposensitive (BHR) guinea pigs were compared. For this purpose, AChE activities were determined by measuring the rate of absorbance of tissue homogenate. Relative amounts of AChE mRNA were also evaluated by the RT-PCR method. In both tracheal smooth muscle and lung tissue from BHS, the AChE activity and the relative amount of AChE mRNA were less than those in BHR. These results suggest that the reduced AChE activity is at least a candidate for inducing airway hyperresponsiveness.