1. Effect of N-WASp glutathione-S-transferase (GST) fusion proteins on force in tracheal muscle strips stimulated with 10−5 M ACh under isometric conditions.
Effect of N-WASp glutathione-S-transferase (GST) fusion proteins on force in tracheal muscle strips stimulated with 10−5 M ACh under isometric conditions. A: active force in smooth muscle strips treated with GST-tagged N-WASp domains. Representative tracings of three muscle strips from one experiment show that treatment with GST fusion proteins for the CA domain of N-WASp inhibited ACh-induced contraction in smooth muscle strips, whereas treatment with GST fusion proteins for the VCA domain did not depress force. Tissues not treated with proteins exhibited no depression of tension generation. B: mean data for isometric force obtained from 14 smooth muscle strips treated with GST fusion proteins for the N-WASp VCA and CA domains. Active force in response to 10−5 M ACh was quantitated as the percentage of the normalized force in the no protein group. Values are means ± SE; n = 14 experiments. In GST CA domain tissues, the contractile force generated after stimulation with ACh for 5 min was markedly inhibited (69.8 ± 3.8% of preincubation force). The contractile responses were not affected in tissues not treated with protein or in tissues treated with GST VCA fusion proteins. *P < 0.05, significantly different force from that in tissues not treated with proteins and from tissues treated with GST VCA fusion proteins (n = 14). C: representative immunoblot for GST showing that GST VCA and GST CA fusion proteins were present in muscle strips. Immunoblot shown is representative of results from four experiments.
Wenwu Zhang et al. Am J Physiol Cell Physiol 2005;288:C1145-C1160
©2005 by American Physiological Society