title: Transient decrease in gap junction expression during compensatory renal growth in mice.
abstract: OBJECTIVE
  To examine gap junction expression during compensatory renal growth. Compensatory renal growth is a normal response to the removal of renal cells. Gap junctional intercellular communication plays important roles in homeostatic regulation, differentiation, and synchronization of cellular electronic and metabolic functions.
  
  
  METHODS
  The right ureters of 5-week-old ddy mice were dorsally incised and unilaterally obstructed, and the animals were killed at varying intervals. The control group underwent a sham operation. Freeze-fractured kidney tissue samples were studied using electron microscopy. The amount of proliferative cell nuclear antigen-positive cells and connexin 43 (Cx43) protein was studied by immunohistochemistry and Western blotting, respectively.
  
  
  RESULTS
  Proliferative cell nuclear antigen-positive cells in the renal tubules increased on days 1 and 2 after surgery that obstructed the ureter, and decreased to normal levels by day 14. The number of gap junctions significantly decreased on days 1 and 2, and then gradually increased to normal levels from days 3 to 14 after surgery. The amount of Cx43 protein in the renal tubules decreased until day 2 and recovered to the same level as that of the control by day 14 after surgery. Significantly, a hyperphosphorylated band of Cx43 in the control kidney was not detected in the operated kidney.
  
  
  CONCLUSIONS
  These data suggest that the gap junctional intercellular communication of renal tubular cells during compensatory renal growth after unilateral ureteral obstruction could be temporarily reduced concomitant with a decrease of the expression of a phosphorylated Cx43 protein in renal cortical tubular cells after unilateral ureteral obstruction of the contralateral kidney.
authors.affiliation: Department of Urology, Nagasaki University School of Medicine, Nagasaki, Japan.
authors.forename: Shengwen
authors.initials: S
authors.lastname: Li
authors.forename: Koichiro
authors.initials: K
authors.lastname: Nomata
authors.forename: Tomayoshi
authors.initials: T
authors.lastname: Hayashi
authors.forename: Mitsuru
authors.initials: M
authors.lastname: Noguchi
authors.forename: Shigeru
authors.initials: S
authors.lastname: Kanda
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Kanetake
mesh_terms: D000222:Adaptation, Physiological / Q000235:genetics / Q000502:physiology; D000818:Animals; D015153:Blotting, Western; D002478:Cells, Cultured; D018031:Connexin 43 / Q000235:genetics / Q000378:metabolism; D017630:Connexins / Q000235:genetics / Q000378:metabolism; D005614:Freeze Fracturing; D017629:Gap Junctions / Q000235:genetics* / Q000378:metabolism; D015870:Gene Expression / Q000235:genetics; D007150:Immunohistochemistry; D007668:Kidney / Q000166:cytology / Q000254:growth & development*; D051379:Mice; D014517:Ureteral Obstruction / Q000503:physiopathology*
chemical_list: D018031:Connexin 43; D017630:Connexins