Proximal and distal penile-urethral stomas were created in the rabbit
and 1 to 3 months later a free bladder mucosal graft was placed in the
damaged urethral bed. The graft adhered to a rapidly proliferating su
bmucosa with active regeneration by post-transplantation day 5. All gr
afts were adherent and viable by days 10 to 14, during which time sham
operated animals that had been stented only showed a degree of epithe
lial regeneration that was of variable quality and without submucosal
proliferation. The graft may stimulate the subepithelial layer, and th
e most viable bladder mucosa may be associated with the most actively
proliferating subepithelial layer, which is also the area of greatest
neovascularity. Further studies may explain the apparent paradox of ho
w a free bladder mucosal graft survives in a poorly vascularized, scar
red urethral bed.