Connexin 43 expression in normal versus dysfunctional labor

OBJECTIVE: We sought to determine whether connexin 43 (C×43), the major myometrial gap junction protein, is differentially expressed in normal versus dysfunctional labor. STUDY DESIGN: Myometrial biopsies were obtained from 28 patients undergoing cesarean section and grouped into the following categories: (1) no labor, (2) dysfunctional labor, and (3) normal labor. Northern and Western analyses were performed to determine C×43 messenger RNA (mRNA) and protein expression, respectively. Localization of C×43 protein was determined by immunohistochemistry. RESULTS: Labor was associated with increased C×43 mRNA expression (P < .05). This association was not true for protein. There was no difference in mRNA or protein expression between patients with normal labor versus those with dysfunctional labor. The extent of C×43 immunohistochemical staining was not significantly different among the groups (P > .05). CONCLUSION: Dysfunctional labor is not associated with aberrant C×43 mRNA or protein expression or with a reduction in immunodetectable C×43 gap junctions. (Am J Obstet Gynecol 2002;186:504-11.)