Olfactory mucosal transplantation after spinal cord injury improves voiding efficiency by suppressing detrusor-sphincter dyssynergia in rats.
OBJECTIVE
Several recent studies showed that olfactory mucosal transplantation after spinal cord injury promotes extensive regeneration of the injured spinal cord. We examined the efficacy of olfactory mucosal transplantation for bladder dysfunction after spinal cord injury in rats.


METHODS
In adult female rats the Th9-10 spinal cord was completely transected, followed by olfactory mucosal transplantation or gelatin sponge filling as the control. Each group was examined by cystometrogram and external urethral sphincter electromyogram. Calcitonin gene-related peptide and growth associated protein 43 double positive expression in the L6/S1 dorsal horn was evaluated by immunohistochemistry. Transplant sites were examined by immunohistochemistry with antibodies against neurofilament M and neuronal class III beta-tubulin.


RESULTS
On cystometrogram voiding efficiency was significantly higher in the transplantation group than in controls. On external urethral sphincter electromyogram with simultaneous cystometrogram the transplantation group showed a larger ratio of interburst silent periods to burst activity duration and a greater number of high frequency oscillations. In the transplantation group calcitonin gene-related peptide and growth associated protein 43 double positive expression in the L6/S1 dorsal horn was less dense than in controls. The transplantation group showed strong neurofilament M and neuronal class III beta-tubulin expression at the transplant site.


CONCLUSIONS
Olfactory mucosal transplantation after spinal cord injury weakened external urethral sphincter excessive bursting and increased the urethral opening to improve voiding efficiency. Olfactory mucosal transplantation may modify emergence of the spinal micturition reflex after spinal cord injury. Transplantation resulted in new axons growing at the transplant site, implying the possible existence of interneuron bridging across the injured spinal cord.
Nakayama
Jiro
J
Department of Urology, Osaka University Graduate School of Medicine, Suita, Japan.
Takao
Tetsuya
T
Kiuchi
Hiroshi
H
Yamamoto
Keisuke
K
Fukuhara
Shinichiro
S
Miyagawa
Yasushi
Y
Aoki
Masanori
M
Iwatsuki
Koichi
K
Yoshimine
Toshiki
T
Ueno
Masaki
M
Yamashita
Toshihide
T
Nonomura
Norio
N
Tsujimura
Akira
A
Okuyama
Akihiko
A
D000818:Animals; D001259:Ataxia / Q000209:etiology / Q000601:surgery; D005260:Female; D009831:Olfactory Mucosa / Q000637:transplantation*; D051381:Rats; D017207:Rats, Sprague-Dawley; D013119:Spinal Cord Injuries / Q000150:complications / Q000601:surgery*; D001750:Urinary Bladder, Neurogenic / Q000209:etiology / Q000601:surgery*