title: Sex- and age-related changes in connexin 43 expression in normal rat bladder.
abstract: OBJECTIVE
  Gap junctions are intercellular channels to facilitate electrical and metabolic communication between adjacent cells. Connexin 43 is the most predominant type of connexin expressed on rat detrusor muscle cells. We investigated the connexin 43 expressions in various age groups of either sex in normal rats.
  
  
  METHODS
  Eighty Sprague-Dawley rats were used for analysis. Each group was quantified by 8 rats at 1 week, 2 weeks, 1 month, 3 months, and 6 months of age in either sex. In each animal, bladder was removed without any kind of intervention and fresh-frozen in liquid nitrogen. Total RNA extraction was done with easy-BLUE total RNA extraction kit. Reverse transcription polymerase chain reaction was done for connexin 43 and glyceraldehyde-3-phosphate dehydrogenase as an internal control using ImProm-II Reverse Transcription System.
  
  
  RESULTS
  In female rats, no age-related change was detected in connexin 43 expressions. In male rats, connexin expression at 3 months of age showed significant decrease compared with 1 week, 2 weeks, and 6 months of age (P<0.05). When connexin expression at the same age in male and female were compared, only 3 months group in male showed significant decrease than the same age group in female.
  
  
  CONCLUSIONS
  Our data suggest that the expressions of connexin 43 mRNA in normal detrusor muscle cell showed age-related changes especially in male rats. Although it is difficult to interpret these findings at this stage, age should be considered as a possible compounding factor affecting connexin 43 expressions in male rats.
authors.affiliation: Department of Urology, Eulji University College of Medicine, Daejeon, Korea.
authors.forename: Sung Ho
authors.initials: SH
authors.lastname: Song
authors.forename: Hyun Taek
authors.initials: HT
authors.lastname: Joo
authors.forename: Hyeon Wook
authors.initials: HW
authors.lastname: Cho
authors.forename: Ha Wook
authors.initials: HW
authors.lastname: Hwang
authors.forename: Ki Ho
authors.initials: KH
authors.lastname: Lee
authors.forename: Dae Kyung
authors.initials: DK
authors.lastname: Kim