Smooth muscle electromyography of the urinary bladder

Scheepe, Jeroen R.; Wipfler, G.; Schumacher, Stefan; Bross, S.; Zendler, S.; Jünemann, K. P.; Alken, P.

doi:10.1002/(sici)1520-6777(1998)17:1<71::aid-nau9>3.0.co;2-a

Cited by 19 publications

(8 citation statements)

References 23 publications

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“…In our recordings, the vast majority of electrical activities consisted of low-amplitude, high-frequency spikes, often barely above the noise level (41). Neighboring electrodes showed similar rapid deflections, but most were not in synchrony with the deflections at adjacent electrodes, suggesting that local microscopic propagation is very limited, even within the dimension of the tip of a single recording electrode; i.e., 0.30 mm, roughly equivalent to 5-50 cells (23).…”

Section: Discussionmentioning

confidence: 99%

Macroscopic electrical propagation in the guinea pig urinary bladder

Hammad

Stephen

Lubbad

et al. 2014

American Journal of Physiology-Renal Physiology

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There is little knowledge about macroscopic electrical propagation in the wall of the urinary bladder. Recording simultaneously from a large number of extracellular electrodes is one technology that could be used to study the patterns of macroscopic electrical propagations. The urinary bladders from 14 guinea pigs were isolated and placed in an organ bath. A 16 × 4-electrode array was positioned at various sites on the serosal bladder surface, and recordings were performed at different intravesical volumes. In four experiments, carbachol (CCH; 10−6 M), nifedipine (10 mM), or tetrodotoxin (TTX; 10−6 M) was added to the superfusing fluid. After the experiments, the extracellular signals were analyzed and propagation maps were constructed. Electrical waves were detected at all sites on the bladder surface and propagated for a limited distance before terminating spontaneously. The majority of waves (>90%) propagated in the axial direction (i.e., from dome to base or vice versa). An increase in vesicle volume significantly decreased the conduction velocity (from 4.9 ± 1.5 to 2.7 ± 0.7 cm/s; P < 0.05). CCH increased, nifedipine decreased, while TTX had little effect on electrical activities. In addition, a new electrical phenomenon, termed a “patch,” was discovered whereby a simultaneous electrical deflection was detected across an area of the bladder surface. Two types of electrical activities were detected on the bladder surface: 1) electrical waves propagating preferentially in the axial direction and 2) electrical patches. The propagating electrical waves could form the basis for local spontaneous contractions in the bladder during the filling phase.

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Section: Discussionmentioning

confidence: 99%

Macroscopic electrical propagation in the guinea pig urinary bladder

Hammad

Stephen

Lubbad

et al. 2014

American Journal of Physiology-Renal Physiology

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“…Craggs & Stephenson (), Scheepe et al . (, ) and Ballaro et al . () recorded extracellular signals using suction or metal electrodes made mainly from silver or platinum.…”

Section: Characteristics Of Electrical Impulses In Urinary Bladdermentioning

confidence: 91%

Electrical propagation in the renal pelvis, ureter and bladder

Hammad

2014

Acta Physiol

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Under normal conditions, following the passage of urine from the collecting duct, the urine is stored briefly in the renal pelvis before being transported through the ureter to the bladder where the urine is stored for a longer time (hours) before being voided through the urethra. The transport of urine from the renal pelvis to the bladder occurs spontaneously due to contractions of the muscles in the wall of the pelvis and ureter. Spontaneous contractions also occur in the detrusor muscle and are responsible for maintaining the bladder shape during the filling phase. These muscle contractions occur as result of electrical impulses, which are generated and propagated through different parts of the urinary tract. The renal pelvis and the ureter differ from the bladder in relation to the origin, characteristics and propagation of these electrical impulses. In the ureter, the electrical impulses originate mainly at the proximal region of the renal pelvis and are transmitted antegradely down the length of the ureter. The electrical impulses in the bladder, on the other hand, originate at any location in the bladder wall and can be transmitted in different directions with the axial direction being the prominent one. In this manuscript, an overview of the current state of research on the origin and propagation characteristics of these electrical impulses in the normal and pathological conditions is provided.

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“…Note increase in amplitude and frequency of the signal with carbachol (arrow). Reproduced from [26] by permission of Wiley‐Liss Inc.…”

Section: The History Of Detrusor Electromyographymentioning

confidence: 99%