Figure 1.

Activation of muscarinic m3 receptors increases tyrosine phosphorylation of paxillin and FAK. (A–C) Confluent monolayers of HEK cells stably transfected with m3 receptors were treated with 100 μM carbachol or vehicle for various periods of time. (D–F) Cell monolayers were incubated for 10 min in serum-free medium containing various concentrations of carbachol. Cells were lysed, and antiphosphotyrosine immunoprecipitates were analyzed by immunoblotting with antiphosphotyrosine antibodies (A), antibodies to paxillin (B, E), or antibodies to FAK (D). (C, F) Paxillin content of antiphosphotyrosine immunoprecipitates was quantitated by densitometry. Data are expressed as a percentage of the maximal response. Means ± SEM from three to four experiments are shown.