Fig 2: Expression of TRPC channels in ATII cells and complementary roles of TRPC4 and KCa3.1 in wound repair on fibronectin matrix. Representative agarose gel showing PCR products amplified from ATII cDNA with PCR primer pairs designed from rat TRPC channels (a). TRPC channel relative mRNA expressions were normalized to ß-actin and compared between no coating and fibronectin matrix conditions (b, n = 16–20). c. Levels of TRPC4 protein expression in membrane fractions were measured by immunoblotting using specific anti-TRPC4 channel antibody and band intensities were compared between control (no coating) and fibronectin matrix conditions (c, right panel, n = 11). A representative immunoblot is shown in the left panel. d. ATII cells, cultured in the absence (-) or presence (+) of a fibronectin coating, were injured mechanically and the wound-healing rates (µm2/h) over a 24-h period were then compared in control condition (-), in presence of the TRPC4 inhibitor ML-204 (100 µM, +) (n = 8) or a combination of ML-204 (100 µM) and TRAM-34 (20 µM) (d, n = 7). *p < 0.05

Fig 3: Complementary roles of ECM, ß1-integrin, KCa3.1 and TRPC4 channels during alveolar repair process. The presence of fibronectin matrix evokes an increase in membrane expression of ß1-integrin, KCa3.1 and TRPC4, an elevation of steady-state [Ca2+]i and a stimulation of ATII wound healing. This stimulation is dependent, at least in part on KCa3.1 and TRPC4 channel activity. Our data also highlighted a relationship between KCa3.1 and ß1-integrin

Fig 4: Cell-type specific TRPC1, TRPC4, and TRPC5 channel upregulation in the hippocampus and cortex after CCI-TBI. (A,B) Representative Western immunoblots using (A) TRPC4 (~120 kDa) and (B) TRPC5 (~110 kDa) antibodies in sham and TBI cortex and hippocampus. Blots were normalized to ß-actin protein (42 kDa) as loading control. (C,D) Summarized data for Western blot quantification of TRPC4 (C, n = 7–13 animals per group) and TRPC5 (D, n = 5–7 animals per group) from microdissected brain regions in mice 7 days after TBI. (E,F) Shown are summarized plots of percent difference in TRPC4 (E) and TRPC5 (F) protein between ipsilateral and contralateral hemispheres of microdissected regions from data in Panels (C,D). All data bars represent the mean ± SEM. *p < 0.05 vs. sham of same subregion. †p < 0.05 vs. contralateral hemisphere of same subregion.

Fig 5: TRPC4/TRPC5 channel activation artificially prolongs Ca2+ influx in DGGCs after CCI-TBI. (A) Cumulative probability distribution of the peak amplitude of GCaMP6f fluorescence (?F/F) for each DGGC from sham (control) and iTBI slices during EA (1 µM, red) or EA + M084 (10 µM, gray) application. (B) Cumulative probability distribution of the Ca2+ influx duration (in seconds) for each DGGC from control and iTBI slices during EA or EA + M084 application. (C,D) Histogram population distribution of control DGGC Ca2+ influx events according to peak amplitude (C) and Ca2+ event duration (D). (E,F) Histogram population distribution of iTBI DGGC Ca2+ influx events according to peak amplitude (E) and Ca2+ event duration (F). (G) Summarized means of peak fluorescence from data as in Panel (A). (H) Summarized means of Ca2+ influx duration from data as in Panel (B). Red = EA alone, gray = EA + M084. All data bars represent the mean ± SEM. *p < 0.05 vs. EA alone from same procedure condition, †p < 0.05 vs. control of same drug condition.