PMID- 14559447
OWN - NLM
STAT- MEDLINE
DCOM- 20031112
LR  - 20190817
IS  - 0022-4804 (Print)
IS  - 0022-4804 (Linking)
VI  - 114
IP  - 2
DP  - 2003 Oct
TI  - Effect of bladder outlet obstruction on detrusor smooth muscle cell: an in vitro 
      study.
PG  - 202-9
AB  - BACKGROUND: Although relieving obstruction is generally curative on bladder 
      outlet obstruction (BOO), bladder dysfunction persists in some patients. 
      Repetitive stretch and relaxation applied to cultured bladder smooth muscle (SM) 
      cells in vitro have been used to mimic increases in urodynamic load experienced 
      by the detrusor muscle under conditions of BOO. We first clarified the 
      relationship between phenotype transformation and biomechanical properties of 
      detrusor smooth muscle cell (DSMC) subjected to the cyclic mechanical stretch. 
      MATERIALS AND METHODS: Cultured rat DSMC were grown on collagen-coated silicone 
      membranes and subjected to continuous cycles of stretch-relaxation. All 
      experiments were performed on cells between passages 2 and 4. Each cycle consists 
      of 5 seconds of stretch and 5 seconds of relaxation. The computer controlled 
      vacuum induced 10% (1), 20% (2), and 30% (3) maximum elongation of the plate 
      membrane at different designed pressures. The deoxyribonucleic acid synthesis 
      rate was assessed by performing tritiated thymidine incorporation assay. The 
      expression of SM-alpha-actin and proliferation of DSMC were analyzed by 
      immunofluorescent assay and flow cytometry. The image analysis and micropipet 
      aspiration systems were used to investigate the single cell contraction and 
      viscoelasticity. Using the 3-element standard linear solid model, the elastic 
      modulus K(1), K(2), and viscoelastic coefficient mu were determined, which show 
      the passive deformation ability of detrusor cells. RESULTS: As the basic 
      structural changes to mechanical stretch, DSMC undergo phenotypic modulation from 
      their normal contractile phenotype to a "synthetic" phenotype: the DSMC become 
      more proliferative and the actin less organized along the cell's long axis. The 
      cell proliferation index of control and stretched group (10%, 20%, 30% 
      elongation) are 0.24, 0.43, 0.58, and 0.65, respectively. The actin filaments in 
      unstimulated cells were evident and orientated along the major axis of the cell. 
      After mechanical stretch, the well-spread filaments changed their orientation. 
      The function, such as contraction, and viscoelasticity of a single DSMC subjected 
      to stretch both decreased significantly compared with control. The maximum 
      contractile velocity and maximum cell length shortening rate of group 3 (30% 
      elongation) showed significant decreases compared with unstretched control (P < 
      0.01). K(1) and K(2) were decreased with the increase of mechanical overload. 
      However, there was no statistic difference between groups 2 and 3. CONCLUSIONS: 
      Functional abnormalitie of BOO have the structural basis: phenotype 
      transformation (i.e., remodeling) of the detrusor cells. Cyclic stretch and 
      relaxation applied to DSMC in vitro can be used to model increases in urodynamic 
      load experienced by the bladder detrusor muscle under conditions of BOO. 
      Phenotype transformation is the structural basis of functional changes of DSMC 
      subjected to periodic overload mechanical stretch.
FAU - Yu, Gong
AU  - Yu G
AD  - Urologic Center, Southwest Hospital, Third Military Medical University, 
      Chongqing, People's Republic of China. gongyu2009@sina.com
FAU - Bo, Song
AU  - Bo S
FAU - Xiyu, Jin
AU  - Xiyu J
FAU - Enqing, Xiong
AU  - Enqing X
LA  - eng
PT  - Journal Article
PT  - Research Support, Non-U.S. Gov't
PL  - United States
TA  - J Surg Res
JT  - The Journal of surgical research
JID - 0376340
RN  - 0 (Actins)
RN  - 0 (Silicones)
SB  - IM
MH  - Actins/genetics
MH  - Animals
MH  - Cell Cycle/physiology
MH  - Cell Division
MH  - Cells, Cultured
MH  - DNA Replication/physiology
MH  - Disease Models, Animal
MH  - Elasticity
MH  - Male
MH  - Muscle Contraction/physiology
MH  - Muscle Relaxation/physiology
MH  - Muscle, Smooth/cytology/pathology/*physiopathology
MH  - Rats
MH  - Rats, Wistar
MH  - Silicones
MH  - Urinary Bladder Neck Obstruction/*physiopathology
MH  - Viscosity
EDAT- 2003/10/16 05:00
MHDA- 2003/11/13 05:00
CRDT- 2003/10/16 05:00
PHST- 2003/10/16 05:00 [pubmed]
PHST- 2003/11/13 05:00 [medline]
PHST- 2003/10/16 05:00 [entrez]
AID - S0022480403003330 [pii]
AID - 10.1016/s0022-4804(03)00333-0 [doi]
PST - ppublish
SO  - J Surg Res. 2003 Oct;114(2):202-9. doi: 10.1016/s0022-4804(03)00333-0.