Figure 5.

Differences in pulsation frequency were observed in the co-culture system. (A) TBX18-CFs improved the beating rate of NRVMs in the co-culture system. The frequency of spontaneous beating of TBX18-CFs+NRVMs was significantly higher than that of the other groups. The (B) beating rates, and the (C) minimum and (D) maximum beating rates were compared in each group. The beating frequency of TBX18-NRVMs increased by ~40 to 132 bpm (depending on the conditions) when TBX18-NRVMs were co-cultured with TBX18-CFs. Bar 1, NRVMs; bar 2, TBX18-NRVMs; bar 3, TBX18-NRVMs+CFs; bar 4, TBX18-NRVMs+GFP-CFs; and bar 5, TBX18-NRVMs+TBX18-CFs. **P<0.01, as indicated. TBX18, T-box18; CFs, cardiac fibroblasts; NRVMs, neonatal rat ventricular cardiomyocytes; GFP, green fluorescence protein; bpm, beats per minute.