Cyclic Stretching Influenced Connexin43 of Human Periodontal Ligament Cells

Objectives: The present research aimed to study the effect of cyclic stretching on connexin43 (Cx43) and its mRNA of human periodontal ligament (PDL) cells, thus to explore the effect of mechanical stretching on the gap junction of human PDL cells.

Methods: The human PDL cells were obtained from healthy premolars. After three to five passages, the cells were stretched by 1%, 10% and 20% strain for 30 min, 1 h, and 24 h. Then Cx43 on the cell membrane was detected by flow cytometry and Cx43 mRNA level was measured by Real-time PCR.

Results: After being loaded with 10% and 20% stretching strain for 24h, the percentage of human PDL cells with membrane Cx43 decreased from 73.10%±2.95% to 60.80%±2.71% (10% strain for 24h) and 27.68%±2.62% (20% strain for 24h) respectively. Cx43 mRNA level decreased after being loaded with 1%, 10% and 20% stretching strain for 30 min and increased after being loaded for 1h. Cx43 mRNA level of cells loaded with 1% strain for 24h was lower than that of control cells. While Cx43 mRNA levels of cells loaded with 10% and 20% strain for 24h were higher than that of control cells.

Conclusion: Results of this research show that cyclic stretching could affect the membrane Cx43 protein and Cx43 mRNA level of human PDL cells. Gap junction might have played a role in the response of human PDL cells to cyclic stretching.

This research is supported by Shanghai Leading Academic Discipline Project (No. T0202), Postdoctoral scientific research fund of China (No. 2005037137), and the fund from Shanghai Education Committee (No. Jiaofa-0501).