Intrathecal or dietary glycine inhibits bladder and urethral activity in rats with spinal cord injury.
OBJECTIVE
We examined the influence of intrathecal or dietary glycine on bladder and urethral activity in rats with spinal cord injury.


METHODS
A total of 20 female Sprague-Dawley rats were used 4 weeks after lower thoracic spinal cord injury. The rats were divided into standard and 1% glycine diet groups. In the standard diet group isovolumetric cystometry and urethral pressure measurement were performed before and after intrathecal injection of glycine. In the 1% glycine diet group bladder and urethral activity were compared with control recordings in the standard diet group.


RESULTS
In the standard diet group intrathecal injection of glycine prolonged the interval and decreased the amplitude of bladder contractions, decreased baseline urethral pressure and altered urethral activity during bladder contraction from a pattern of detrusor-sphincter dyssynergia to detrusor-sphincter synergy at 100 mug glycine. In the 1% glycine diet group the interval and amplitude of bladder contractions were prolonged and decreased, respectively, compared with those in the standard diet group. Baseline urethral pressure was lower than in the standard diet group even after intrathecal injection of 100 mug glycine. Urethral pressure did not change during bladder contraction and it was the same as baseline pressure. Residual urine volume was lower than in the standard diet group.


CONCLUSIONS
Intrathecal or dietary glycine inhibits bladder and urethral activity, and improves detrusor hyperreflexia and detrusor-sphincter dyssynergia.
Miyazato
Minoru
M
Department of Urology, Faculty of Medicine, University of the Ryukyus, 207 Uehara, Nishihara, Okinawa 903-0215, Japan.
Sugaya
Kimio
K
Nishijima
Saori
S
Kadekawa
Katsumi
K
Ashimine
Satoshi
S
Ogawa
Yoshihide
Y
D000284:Administration, Oral; D000818:Animals; D001835:Body Weight; D019587:Dietary Supplements; D004195:Disease Models, Animal; D004305:Dose-Response Relationship, Drug; D005260:Female; D005998:Glycine / Q000008:administration & dosage / Q000494:pharmacology*; D018684:Glycine Agents / Q000008:administration & dosage / Q000494:pharmacology*; D007278:Injections, Spinal; D007537:Isometric Contraction / Q000187:drug effects; D051381:Rats; D017207:Rats, Sprague-Dawley; D013119:Spinal Cord Injuries / Q000503:physiopathology*; D013904:Thoracic Vertebrae / Q000473:pathology / Q000503:physiopathology; D014521:Urethra / Q000187:drug effects* / Q000503:physiopathology; D001743:Urinary Bladder / Q000187:drug effects* / Q000503:physiopathology; D014554:Urination / Q000187:drug effects
D018684:Glycine Agents; D005998:Glycine