The passive and active contractile properties of the neurogenic, underactive bladder.
BJU Int
; 111(2): 355-61, 2013 Feb.
Article
em En
| MEDLINE
| ID: mdl-22712666
ABSTRACT
OBJECTIVE:
To characterize passive and active changes in detrusor activity in a highly compliant bladder. MATERIALS ANDMETHODS:
Bladders from adult female Sprague-Dawley rats were used 5 weeks after lower thoracic (T8) spinal cord transection or a sham-operation. Passive wall properties were assessed by pressure-volume relationships from whole bladders and the tensile response of bladder strips after a rapid (<0.5 s) stretch. Active properties were assessed from the frequency and amplitude of spontaneous contractions of bladder strips, and their response to the inotropic TRPV4 agonist GSK1016790A.RESULTS:
Passive bladder wall stiffness of SCT bladders was significantly reduced compared to that of the sham-operated control group (N = 6 and 8, respectively) and SCT bladder strips relaxed more quickly than those from sham-operated rats. The frequency of spontaneous contractions was reduced in SCT rats, and their amplitude, expressed as a ratio of bladder wall stiffness, was greater than in sham-operated rats. GSK1016790A (0.1 µM) significantly increased amplitude in strips from both sham-operated and SCT groups.CONCLUSIONS:
There is no evidence of contractile failure in a highly-compliant bladder. The observations of reduced passive bladder wall stiffness and an enhanced rate of stress relaxation lead to the conclusion that increased compliance is marked by altered matrix properties that dissipate muscle force, thereby generating low pressures. Contractile agonists may be effective for improving bladder function in detrusor underactivity.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Bexiga Urinária
/
Bexiga Urinaria Neurogênica
/
Contração Isométrica
/
Músculo Liso
Tipo de estudo:
Etiology_studies
Limite:
Animals
Idioma:
En
Revista:
BJU Int
Assunto da revista:
UROLOGIA
Ano de publicação:
2013
Tipo de documento:
Article
País de afiliação:
Reino Unido