811 IN VITRO FUNCTIONAL STUDY OF CHLORIDE CHANNELS ON RAT BLADDER SMOOTH MUSCLE

Our understanding of the pathophysiology of the overactive bladder is poor. It has been proposed that localized contractions result in the abnormal stretching of bladder smooth muscle. We hypothesize that stretch regulates the cellular processes that determine tissue size. The purpose of this study was to investigate the effect of stretch on apoptosis, proliferation, cell hypertrophy, and growth factor production in human bladder smooth muscle cells in vitro. Normal human detrusor muscle was obtained from patients undergoing radical cystectomy for invasive bladder cancer, and primary cultures were established. Cells were mechanically stretched on flexible plates at a range of pressures and times. Apoptosis was assessed by propidium iodide incorporation and flow cytometry. Radiolabeled thymidine and amino acid incorporation were used to assess proliferation and cell hypertrophy. ELISA and RT-PCR were used to assess growth factor production. Mechanical stretch inhibits apoptosis in a time- and dose-dependent manner and was associated with increases in the antiapoptotic proteins heat shock protein-70 and cIAP-1. Stretch also increases smooth muscle cell proliferation and hypertrophy, but hypertrophy is the more dominant response. These changes were associated with increases in IGF-1 and basic FGF and a decrease in transforming growth factor-β1. Mechanical stretch regulates apoptosis, proliferation, and cell hypertrophy in human bladder smooth muscle cells.

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Structural and functional study of control of canine tracheal smooth muscle

AJP Cell Physiology ◽

10.1152/ajpcell.1980.238.1.c27 ◽

1980 ◽

Vol 238 (1) ◽

pp. C27-C33 ◽

Cited By ~ 26

Author(s):

M. S. Kannan ◽

E. E. Daniel

Keyword(s):

Smooth Muscle ◽

Electrical Field Stimulation ◽

Sympathetic Nerves ◽

Tracheal Smooth Muscle ◽

Functional Study ◽

Field Stimulation ◽

Electron Microscopic ◽

Microscopic Studies ◽

Stimulation Of

The structural bases for myogenic and neurogenic control of canine tracheal smooth muscle were studied. At optimum lengths, strips of muscle showed insignificant neurogenic or myogenic tone. Atropine and/or tetrodotoxin blocked the contractile responses elicited on electrical field stimulation of intrinsic nerves. After raising the tone with tetraethylammonium ion and in the presence of atropine, field stimulation of nerves caused a relaxation, a major component of which was blocked by propranolol and/or tetrodotoxin, suggesting an effect mediated through interaction of mediator released from sympathetic nerves with beta-adrenergic receptors. Electron microscopic studies revealed gap junctions between extensions of smooth-muscle cells and a sparse innervation. The axonal varicosities, corresponding to cholinergic (predominantly) and adrenergic (occasionally) nerves, were seen predominantly in the clefts between cell bundles. The physiological responses were compared with the morphological features. Although this muscle exhibits multiunit behavior in vitro, implying that nerves initiate the coordinate activity, its ultrastructural features suggest a potential for single-unit behavior.

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Protective Effects of Antimuscarinics on the Bladder Remodeling After Bladder Outlet Obstruction

Cellular Physiology and Biochemistry ◽

10.1159/000485358 ◽

2017 ◽

Vol 44 (3) ◽

pp. 907-919 ◽

Cited By ~ 7

Author(s):

Qiang Liu ◽

Deyi Luo ◽

Tongxin Yang ◽

Banghua Liao ◽

Hong Li ◽

...

Keyword(s):

Smooth Muscle ◽

Bladder Outlet Obstruction ◽

Outlet Obstruction ◽

Structure And Function ◽

Bladder Function ◽

Bladder Smooth Muscle ◽

M3 Receptors ◽

And Function

Background/Aims: Overactive bladder associated with bladder outlet obstruction (BOO) is a highly prevalent condition, which is usually treated with antimuscarinics. However, the potential effects of antimuscarinics on the structure and function of bladder have not been investigated thus far. Methods: Sprague-Dawley(R) rats accepted bladder neck obstruction surgery or sham surgery, and then received treatment of three different antimuscarinics (Solifenacin, Darifenacin, and Tolterodine) or vehicle. After 3, 6 and 12 weeks, the bladder function and structure were measured. The effect of antimuscarinics on cellular alteration in vitro was observed under mechanical stimulation. Bladder morphology were examined by immunohistochemistry, and the bladder function were investigated by cystometry and strip contractility test. The expression of muscarinic receptors and inflammatory cytokines were measured by PCR and Western blotting. Results: Here we demonstrate, both in vitro and in vivo, that antimuscarinics are protective regulators for the bladder structure and function. Antimuscarinics decrease the weight of bladders with BOO. Antimuscarinics improve the voiding parameter and enhance the contraction of bladder smooth muscle. The results also show that antimuscarinics inhibit the proliferation of bladder smooth muscle cells both in vivo and in vitro, it can reduce the collagen deposition and inflammatory cytokines in bladders with BOO. During this process, the expression of M2 and M3 receptors was altered by antimuscarinics. Conclusion: Antimuscarinics could reverse the structural and functional changes of BOO bladder wall at cellular and tissue level, and the alteration of M2 and M3 receptors may be involved in this biological process.

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CHARACTERIZATION OF CULTURED BLADDER SMOOTH MUSCLE CELLS: ASSESSMENT OF IN VITRO CONTRACTILITY

The Journal of Urology ◽

10.1016/s0022-5347(05)68237-7 ◽

1999 ◽

Vol 162 (5) ◽

pp. 1779-1784 ◽

Cited By ~ 54

Author(s):

BRADLEY P. KROPP ◽

YUANYUAN ZHANG ◽

JAMES J. TOMASEK ◽

RICK COWAN ◽

PETER D. FURNESS ◽

...

Keyword(s):

Smooth Muscle ◽

Smooth Muscle Cells ◽

Muscle Cells ◽

Bladder Smooth Muscle

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PTHrP Is Endogenous Relaxant for Spontaneous Smooth Muscle Contraction in Urinary Bladder of Female Rat

Endocrinology ◽

10.1210/en.2012-2142 ◽

2013 ◽

Vol 154 (6) ◽

pp. 2058-2068 ◽

Cited By ~ 7

Author(s):

Nobuyuki Nishikawa ◽

Akihiro Kanematsu ◽

Hiromitsu Negoro ◽

Masaaki Imamura ◽

Yoshio Sugino ◽

...

Keyword(s):

Smooth Muscle ◽

Smooth Muscle Cells ◽

Muscle Cells ◽

Female Rats ◽

Functional Study ◽

Intracellular Camp ◽

Organ Bath ◽

Female Rat ◽

Bladder Smooth Muscle ◽

Bladder Distension

Abstract Acute bladder distension causes various morphologic and functional changes, in part through altered gene expression. We aimed to investigate the physiologic role of PTHrP, which is up-regulated in an acute bladder distension model in female rats. In the control Empty group, bladders were kept empty for 6 hours, and in the Distension group, bladders were kept distended for 3 hours after an artificial storing-voiding cycle for 3 hours. In the Distention group bladder, up-regulation of transcripts was noted for 3 genes reported to be up-regulated by stretch in the cultured bladder smooth muscle cells in vitro. Further transcriptome analysis by microarray identified PTHrP as the 22nd highest gene up-regulated in Distension group bladder, among more than 27 000 genes. Localization of PTHrP and its functional receptor, PTH/PTHrP receptor 1 (PTH1R), were analyzed in the untreated rat bladders and cultured bladder cells using real-time RT-PCR and immunoblotting, which revealed that PTH1R and PTHrP were more predominantly expressed in smooth muscle than in urothelium. Exogenous PTHrP peptide (1-34) increased intracellular cAMP level in cultured bladder smooth muscle cells. In organ bath study using bladder strips, the PTHrP peptide caused a marked reduction in the amplitude of spontaneous contraction but caused only modest suppression for carbachol-induced contraction. In in vivo functional study by cystometrogram, the PTHrP peptide decreased voiding pressure and increased bladder compliance. Thus, PTHrP is a potent endogenous relaxant of bladder contraction, and autocrine or paracrine mechanism of the PTHrP-PTH1R axis is a physiologically relevant pathway functioning in the bladder.

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Simulation of In Vitro-Like Electrical Activities in Urinary Bladder Smooth Muscle Cells

Journal of Biomimetics Biomaterials and Biomedical Engineering ◽

10.4028/www.scientific.net/jbbbe.33.45 ◽

2017 ◽

Vol 33 ◽

pp. 45-51

Author(s):

Chitaranjan Mahapatra ◽

Rohit Manchanda

Keyword(s):

Smooth Muscle ◽

Urinary Bladder ◽

Neurotransmitter Release ◽

Compartment Model ◽

Bladder Smooth Muscle ◽

Parasympathetic Nerve ◽

Stochastic Nature ◽

Urinary Bladder Smooth Muscle ◽

Electrical Activities

Urinary bladder smooth muscle (UBSM) generates spontaneous electrical activities due to stochastic nature of purinergic neurotransmitter release from the parasympathetic nerve. The stochastic nature of the purinergic neurotransmitter release was represented by a simplified ‘point-conductance’ model to mimic in vitro-like electrical activities in UBSM cell. The point-conductance was represented by the independent synaptic conductance described by the stochastic random-walk processes and injected into a single-compartment model of mouse UBSM cell. This model successfully evoked irregular spontaneous depolarizations (SDs) and spontaneous action potential (sAP) as the properties of in vitro-like electrical activities in UBSM cells. The model mimics the T- and L-type Ca2+ ion channel blocker by setting their respective conductance to zero. We also found that the point-conductance model modulates the sAP properties by adding background activity.

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In Vitro Biocompatibility Evaluation Of Naturally Derived And Synthetic Biomaterials Using Normal Human Bladder Smooth Muscle Cells

The Journal of Urology ◽

10.1097/00005392-200204000-00097 ◽

2002 ◽

pp. 1867-1871 ◽

Cited By ~ 7

Author(s):

JEAN-LOUIS PARIENTE ◽

BYUNG-SOO KIM ◽

ANTHONY ATALA

Keyword(s):

Smooth Muscle ◽

Smooth Muscle Cells ◽

Muscle Cells ◽

Bladder Smooth Muscle ◽

Human Bladder ◽

In Vitro Biocompatibility ◽

Normal Human

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A Novel In-Vitro System for the Simultaneous Exposure of Bladder Smooth Muscle Cells to Mechanical Strain and Sustained Hydrostatic Pressure

Journal of Biomechanical Engineering ◽

10.1115/1.1449903 ◽

2002 ◽

Vol 124 (2) ◽

pp. 208-213 ◽

Cited By ~ 14

Author(s):

Karen M. Haberstroh ◽

Martin Kaefer ◽

Natacha DePaola ◽

Sarah A. Frommer ◽

Rena Bizios

Keyword(s):

Smooth Muscle ◽

Hydrostatic Pressure ◽

Smooth Muscle Cells ◽

Collagen Type ◽

Mechanical Strain ◽

Muscle Cells ◽

Collagen Type Iii ◽

Bladder Smooth Muscle ◽

Simultaneous Exposure

The novel hydrostrain system was designed in an effort to establish and maintain conditions that simulate the in-vivo mechanical environment of the bladder. In this laboratory system, ovine bladder smooth muscle cells on flexible, 10-cm-dia silastic membranes were exposed simultaneously to hydrostatic pressure (40 cm H2O, a pressure level currently associated with bladder pathologies) and mechanical strains (up to 25 percent) under standard cell culture conditions for 7 h. Under these conditions, Heparin Binding-Epidermal Growth Factor and Collagen Type III mRNA expression were significantly increased (p<0.01 and 0.1, respectively); however, no changes were observed in Collagen Type I mRNA expression. Decreases in the Collagen Type I:Type III ratio following simultaneous exposure of bladder smooth muscle cells to pathological levels of hydrostatic pressure and mechanical strain in vitro are in agreement with clinically observed increases in Collagen Type III with concomitant decreased human bladder compliance. The results of the present study, therefore, provide cellular/molecular level information relevant to bladder pathology that could have significant implications in the field of clinical urology.

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