Temporal differentiation and maturation of regenerated rat urothelium.
OBJECTIVE
To determine if porcine small intestinal submucosa (SIS)-regenerated urothelium expresses markers of urothelial differentiation, uroplakin and zona occludens-1 (ZO-1), and whether their expression correlates with the histological appearance of the urothelium.


METHODS
In all, 15 rats underwent partial cystectomy and bladder replacement with SIS. Regenerated bladders were harvested at either 2, 7, 14, 28, or 56 days after SIS grafting. Histological examination with haematoxylin and eosin staining was conducted to assess tissue regeneration. Immunohistochemistry was performed with uroplakin and ZO-1 antibodies.


RESULTS
By 14 days after SIS grafting, the urothelial layer was completely confluent over the SIS. Expression of uroplakin and ZO-1, evident at 2 days after SIS grafting, progressed from a cytoplasmic pattern of expression to a mature pattern of cytoplasmic and membrane expression by 56 days after SIS grafting.


CONCLUSIONS
In vivo tissue regeneration produces histologically and phenotypically mature urothelium within 2 weeks of SIS implantation. Regeneration of functional urothelium is probably essential for the subsequent development of the remaining bladder.
Roth
Christopher C
CC
Department of Urology, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73104, USA.
Bell
Cardin H
CH
Woodson
Benjamin
B
Schultz
Andrew D
AD
Palmer
Blake W
BW
Frimberger
Dominic
D
Fung
Kar-Ming
KM
Lin
Hsueh-Kung
HK
Kropp
Bradley P
BP
D000818:Animals; D002454:Cell Differentiation; D005260:Female; D008565:Membrane Proteins / Q000378:metabolism*; D010750:Phosphoproteins / Q000378:metabolism*; D051381:Rats; D017207:Rats, Sprague-Dawley; D012038:Regeneration / Q000502:physiology*; D013552:Swine; D023822:Tissue Engineering / Q000379:methods*; D001743:Urinary Bladder / Q000166:cytology / Q000502:physiology*; D019459:Urothelium / Q000166:cytology / Q000502:physiology*; D062826:Zonula Occludens-1 Protein
D008565:Membrane Proteins; D010750:Phosphoproteins; C569044:Tjp1 protein, rat; D062826:Zonula Occludens-1 Protein