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A non-anesthetized mouse model for recording sensory urinary bladder activity.

Zvara P, Wright AJ, Roach K, Ursiny M, Shapiro B, Dagrosa LM, Nelson MT, Heppner TJ - Front Neurol (2010)

Bottom Line: Intravesical infusion of 0.5% acetic acid reduced the intermicturition interval.This was associated with a 2.1-fold increase in bladder pressure during filling and a two-fold increase at both threshold and micturition pressures.Subsequent intravesical infusion of capsazepine in 0.5% acetic acid reduced filling and threshold pressures by 21 and 31.2%, respectively, and produced corresponding decreases of 36 and 23.4% in sensory nerve activity.

View Article: PubMed Central - PubMed

Affiliation: Department of Surgery, University of Vermont College of Medicine Burlington, VT, USA.

ABSTRACT
The goal of this study was to develop an in vivo awake mouse model for extracellular bladder sensory nerve recording. A bipolar 125-μm silver electrode was positioned under a single postganglionic bladder nerve. Efferent nerve signals were eliminated by tying off the postganglionic bladder nerve between the major pelvic ganglion and the recording electrode. Sensory nerve activity was measured in the conscious animals 48 h after surgery during continuous intravesical infusion of 0.9% saline/0.5% acetic acid followed by 0.5% acetic acid with capsazepine (10 μM) at a rate of 0.75 ml/h. Continuous infusion of 0.9% NaCl led to a gradual increase in the frequency of sensory nerve firing that peaked upon reaching threshold pressure. Non-micturition contractions were observed in some animals during filling and other animals exhibited only minimal pressure fluctuations; both types of events were associated with a rise in sensory nerve activity. Intravesical infusion of 0.5% acetic acid reduced the intermicturition interval. This was associated with a 2.1-fold increase in bladder pressure during filling and a two-fold increase at both threshold and micturition pressures. Concurrent with these changes, sensory activity increased 2.8-fold during filling and 2.4-fold at threshold pressure. Subsequent intravesical infusion of capsazepine in 0.5% acetic acid reduced filling and threshold pressures by 21 and 31.2%, respectively, and produced corresponding decreases of 36 and 23.4% in sensory nerve activity. The current study shows that multifiber sensory nerve recordings can be reproducibly obtained from conscious mice.

No MeSH data available.


Related in: MedlinePlus

Continuous recording of bladder pressure and afferent nerve activity. Infusion of 0.9% NaCl led to regular micturition cycles with steady pressure during filling. 0.5% acetic acid led to higher micturition frequency, multiple non-voiding contractions along with elevated filling, threshold and micturition pressures. This change in bladder function was associated with increased nerve activity. Addition of capsazepine to the acetic acid solution reduced the number of non-voiding contractions and nerve activity. The rectangles mark the points in the experiment where the infusate was changed (M, micturition event).
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Figure 3: Continuous recording of bladder pressure and afferent nerve activity. Infusion of 0.9% NaCl led to regular micturition cycles with steady pressure during filling. 0.5% acetic acid led to higher micturition frequency, multiple non-voiding contractions along with elevated filling, threshold and micturition pressures. This change in bladder function was associated with increased nerve activity. Addition of capsazepine to the acetic acid solution reduced the number of non-voiding contractions and nerve activity. The rectangles mark the points in the experiment where the infusate was changed (M, micturition event).

Mentions: Intravesical infusion of 0.5% acetic acid evoked a significant reduction in intermicturition intervals coupled with an increase in average filling and threshold pressures. The same mouse utilized for the basal and acetic acid urodynamic comparison was further challenged with a mixture of 0.5% acetic acid and 10 μM capsazepine (Figure 3). In the presence of capsazepine, the bladder response to acetic acid was reduced as evidenced by an increase in intermicturition interval and a reduction in filling and threshold pressures.


A non-anesthetized mouse model for recording sensory urinary bladder activity.

Zvara P, Wright AJ, Roach K, Ursiny M, Shapiro B, Dagrosa LM, Nelson MT, Heppner TJ - Front Neurol (2010)

Continuous recording of bladder pressure and afferent nerve activity. Infusion of 0.9% NaCl led to regular micturition cycles with steady pressure during filling. 0.5% acetic acid led to higher micturition frequency, multiple non-voiding contractions along with elevated filling, threshold and micturition pressures. This change in bladder function was associated with increased nerve activity. Addition of capsazepine to the acetic acid solution reduced the number of non-voiding contractions and nerve activity. The rectangles mark the points in the experiment where the infusate was changed (M, micturition event).
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC3008862&req=5

Figure 3: Continuous recording of bladder pressure and afferent nerve activity. Infusion of 0.9% NaCl led to regular micturition cycles with steady pressure during filling. 0.5% acetic acid led to higher micturition frequency, multiple non-voiding contractions along with elevated filling, threshold and micturition pressures. This change in bladder function was associated with increased nerve activity. Addition of capsazepine to the acetic acid solution reduced the number of non-voiding contractions and nerve activity. The rectangles mark the points in the experiment where the infusate was changed (M, micturition event).
Mentions: Intravesical infusion of 0.5% acetic acid evoked a significant reduction in intermicturition intervals coupled with an increase in average filling and threshold pressures. The same mouse utilized for the basal and acetic acid urodynamic comparison was further challenged with a mixture of 0.5% acetic acid and 10 μM capsazepine (Figure 3). In the presence of capsazepine, the bladder response to acetic acid was reduced as evidenced by an increase in intermicturition interval and a reduction in filling and threshold pressures.

Bottom Line: Intravesical infusion of 0.5% acetic acid reduced the intermicturition interval.This was associated with a 2.1-fold increase in bladder pressure during filling and a two-fold increase at both threshold and micturition pressures.Subsequent intravesical infusion of capsazepine in 0.5% acetic acid reduced filling and threshold pressures by 21 and 31.2%, respectively, and produced corresponding decreases of 36 and 23.4% in sensory nerve activity.

View Article: PubMed Central - PubMed

Affiliation: Department of Surgery, University of Vermont College of Medicine Burlington, VT, USA.

ABSTRACT
The goal of this study was to develop an in vivo awake mouse model for extracellular bladder sensory nerve recording. A bipolar 125-μm silver electrode was positioned under a single postganglionic bladder nerve. Efferent nerve signals were eliminated by tying off the postganglionic bladder nerve between the major pelvic ganglion and the recording electrode. Sensory nerve activity was measured in the conscious animals 48 h after surgery during continuous intravesical infusion of 0.9% saline/0.5% acetic acid followed by 0.5% acetic acid with capsazepine (10 μM) at a rate of 0.75 ml/h. Continuous infusion of 0.9% NaCl led to a gradual increase in the frequency of sensory nerve firing that peaked upon reaching threshold pressure. Non-micturition contractions were observed in some animals during filling and other animals exhibited only minimal pressure fluctuations; both types of events were associated with a rise in sensory nerve activity. Intravesical infusion of 0.5% acetic acid reduced the intermicturition interval. This was associated with a 2.1-fold increase in bladder pressure during filling and a two-fold increase at both threshold and micturition pressures. Concurrent with these changes, sensory activity increased 2.8-fold during filling and 2.4-fold at threshold pressure. Subsequent intravesical infusion of capsazepine in 0.5% acetic acid reduced filling and threshold pressures by 21 and 31.2%, respectively, and produced corresponding decreases of 36 and 23.4% in sensory nerve activity. The current study shows that multifiber sensory nerve recordings can be reproducibly obtained from conscious mice.

No MeSH data available.


Related in: MedlinePlus