Figure 2.

NBAECP inhibits ACH-induced precontraction in TRs. (a) Following cumulative addition of ACH, a TR reached a sustained contraction, which was inhibited following cumulative application of NBAECP. (b) A similar experiment was performed in asthmatic TR. (c) The summary results of NBAECP-induced relaxation in 7 control and 6 asthmatic TRs. The IC₅₀ of NBAECP was 12.2 ± 1.3 μg/mL in control TRs and 12.8 ± 1.2 μg/mL in asthmatic TRs. These results indicated that NBAECP could block ACH-induced sustained contractions in control and asthmatic tracheal smooth muscle.