Modulation of gap junction transcript and protein expression during pregnancy in the rat

Abstract. The expression of three different gap junction transcripts, or, (Cx43), B ~ (Cx39, and B2 (Cx26) was examined in several organs during pregnancy in the rat. In all of the organs that were examined-uterus, ovary, heart, and liver-there was a strong correlation between levels of gap junction mRNA and gap junction antigens that were detected at different stages of pregnancy. A striking change in o ~ transcript levels (a 5.5-fold increase) was detected in the uterine myometrium on the day before parturition. This elevation of the c~, transcript is thought to be associated with the formation of gap junctions that are required for synchronizing the contractility of the myometrial cells during parturition. 2 d before parturition, there was a detectable elevation of/32 transcripts and protein in th