Expression of connexins in porcine buccal pouch mucosa cells during real-time long-term cell proliferation in vitro: a primary culture approach.

In this study we investigated the expression of connexins Cx36, Cx37, Cx40, Cx43, and Cx45 mRNAs during real-time cellular proliferation in vitro. The oral mucosa cells were isolated from 80 pubertal crossbred Landrace gilts. The cells were transferred into primary in vitro culture (IVC) and cultured for 30 days. The cells were collected to RNA isolation after 7, 15 and 30 days of IVC and were checked for their real-time proliferative status using real-time cell analysis (RTCA). We found an increased expression of Cx43 mRNA after 30 days of IVC as compared to control (P<0.05). The expression level of Cx36 was significantly decreased after 30 days. The expression of Cx37, Cx40 and Cx45 mRNAs was not changed. The expression of Cx43 was statistically increased when compared to Cx40, Cx37, Cx45 and Cx36 (P<0.001, for all time periods, respectively). We confirmed the expression of selected connexins in porcine buccal mucosa cells during their long-term primary IVC, which suggests the existence of functional gap junction connections (GJCs) communication network between these cells. We also confirmed the observations of other authors that Cx43 plays a substantial role in GJC structure. However, the increased expression of Cx43 in buccal mucosa cells, accompanied with their proliferation during real-time primary culture, is presented, to our knowledge, for the first time.