Bladder transplantation in rats using FK-506.
OBJECTIVE
We created viable bladder tissue by transplantation with immunosuppression.


METHODS
For bladder transplantation the bladder of newborn Brown-Norway rats was excised and each was transplanted into a pouch created in the distal omentum of a 5-week-old Lewis rat. In 15 group 1 rats no immunosuppressive agent was used. In 20 group 2 rats 0.6 mg./kg. FK-506 daily were given intramuscularly until a predetermined day of harvest. Recipient rats were sacrificed on day 3, 5, 7 or 14 after bladder transplantation, and the bladder grafts were harvested and formalin fixed. Hematoxylin and eosin staining was done to examine bladder graft survival and the degree of rejection, and immunohistochemical testing was performed for assessing the vesical nervous system. In 5 rats in the control group bladder augmentation was performed by anastomosing the bladder graft to the native bladder. Each augmented bladder was harvested 21 days later for histopathological assessment.


RESULTS
Overall bladder graft survival was 96.4%. Each successfully transplanted bladder graft appeared macroscopically as a thin walled cyst. In group 1 all bladder grafts showed rejection with cellular infiltration. In group 2 there was mild rejection in 5 rats and no evidence of rejection in the remaining 15. All group 2 bladder grafts had intact nerve distribution. Bladder augmentation was successful in all 5 cases and the mucosa was normal throughout each augmented bladder.


CONCLUSIONS
Because FK-506 successfully prevents rejection, our technique would appear to have the potential for creating viable bladder tissue that may be used for bladder augmentation in cases of vesical exstrophy or neurogenic bladder.
Yamataka
A
A
Department of Pediatric Surgery, Juntendo University School of Medicine, Tokyo, Japan.
Wang
K
K
Kobayashi
H
H
Lane
G
G
Miyahara
K
K
Sueyoshi
N
N
Miyano
T
T
D000818:Animals; D004195:Disease Models, Animal; D006084:Graft Rejection / Q000517:prevention & control; D006085:Graft Survival; D007166:Immunosuppressive Agents / Q000494:pharmacology*; D007273:Injections, Intramuscular; D016377:Organ Transplantation / Q000379:methods*; D051381:Rats; D011917:Rats, Inbred Lew; D012016:Reference Values; D016559:Tacrolimus / Q000494:pharmacology*; D014181:Transplantation Immunology; D001743:Urinary Bladder / Q000473:pathology / Q000637:transplantation*
D007166:Immunosuppressive Agents; D016559:Tacrolimus