Figure 7. CD148-deficient tracheas show diminished contractility, decreased calcium oscillation frequency, and dysregulated SFK signaling in ASM.

Mouse tracheal rings were isolated and stimulated with MCh (A), and contractile force measurements were made with a force transducer. Data are the mean ± SEM with at least 6 tracheal rings per group. *P < 0.05, ***P < 0.001, 2-way ANOVA. (B) Tracheal smooth muscle samples directly isolated from mice were lysed, ultracentrifuged, separated by SDS-PAGE, and transferred to a membrane. Membranes were probed with antibodies against phosphorylated SRC Y527 (inhibitory tyrosine) and total SRC as a loading control. Data shown in this figure are representative of 4 independent experiments. (C) Densitometry quantification of Western blots showing relative intensity of pSRC Y527 compared with total SRC. **P < 0.01, unpaired 2-tailed Student’s t test. (D) Representative calcium oscillations induced by 50 μM MCh in lung slices from BALB/c WT control (upper panel) and Ptprj^TM–/TM– (lower panel) mice. Final fluorescence values are expressed as ratios (F/F₀), normalized to the fluorescence immediately prior to the addition of an agonist (F₀). (E) Average frequency of calcium oscillations, comparing WT control with Ptprj^TM–/TM– mice. Data include 6 animals per group. Data show the mean ± SD. ***P < 0.001, unpaired 2-tailed Student’s t test.