TY - JOUR
T1 - Effect of a 5-HT 1A receptor agonist (8-OH-DPAT) on the external urethral sphincter activity in the rat
AU - Chen, Shih-Ching
AU - Fan, Wen Jia
AU - Lai, Chien Hung
AU - Jason Chen, Jia Jin
AU - Peng, Chih-Wei
PY - 2012/2
Y1 - 2012/2
N2 - Background/Purpose: This study examined the effects of a 5-HT 1A receptor agonist (8-OH-DPAT) on external urethral sphincter (EUS) activity in urethane-anesthetized rats. Methods: An EUS electromyogram (EMG) and intravesical pressure (IVP) were simultaneously recorded during continuous cystometrographic monitoring, to provide a quantitative evaluation of EUS activity and urethral urodynamics of voiding. Results: When examining the EUS burst activity, durations of the active (AP) and silent periods (SP) as a function of the time axis, respectively, exhibited concave- and convex-shaped curves. The burst discharges of the EUS-EMG were divided into nonvoiding and voiding burst activities based on the oscillation waves of the IVP, which were located in Phases 1 and 2 of the IVP. After 8-OH-DPAT treatment, the entire burst period in Phases 1 to 2 of the IVP was significantly prolonged. The average SP in both Phases 1 and 2 significantly increased but the average APs were not affected. Urodynamic results showed decreases in the volume threshold, contraction amplitude, and residual volume as well as an increase in the contraction duration. In addition, the amplitude of bladder high-frequency oscillatory waves in the IVP and the average urethral flow rate were reduced, but the entire voiding efficiency increased. Conclusion: The influences of 8-OH-DPAT on EUS burst activity and urodynamics were exactly detected by the sophisticated EMG analytic design, and the results could be a reference for the pharmacological treatment of patients with lower urinary tract dysfunction.
AB - Background/Purpose: This study examined the effects of a 5-HT 1A receptor agonist (8-OH-DPAT) on external urethral sphincter (EUS) activity in urethane-anesthetized rats. Methods: An EUS electromyogram (EMG) and intravesical pressure (IVP) were simultaneously recorded during continuous cystometrographic monitoring, to provide a quantitative evaluation of EUS activity and urethral urodynamics of voiding. Results: When examining the EUS burst activity, durations of the active (AP) and silent periods (SP) as a function of the time axis, respectively, exhibited concave- and convex-shaped curves. The burst discharges of the EUS-EMG were divided into nonvoiding and voiding burst activities based on the oscillation waves of the IVP, which were located in Phases 1 and 2 of the IVP. After 8-OH-DPAT treatment, the entire burst period in Phases 1 to 2 of the IVP was significantly prolonged. The average SP in both Phases 1 and 2 significantly increased but the average APs were not affected. Urodynamic results showed decreases in the volume threshold, contraction amplitude, and residual volume as well as an increase in the contraction duration. In addition, the amplitude of bladder high-frequency oscillatory waves in the IVP and the average urethral flow rate were reduced, but the entire voiding efficiency increased. Conclusion: The influences of 8-OH-DPAT on EUS burst activity and urodynamics were exactly detected by the sophisticated EMG analytic design, and the results could be a reference for the pharmacological treatment of patients with lower urinary tract dysfunction.
KW - Cystometrography
KW - Electromyography
KW - Urethral flow rate
KW - Voiding
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U2 - 10.1016/j.jfma.2011.01.003
DO - 10.1016/j.jfma.2011.01.003
M3 - Article
C2 - 22370284
AN - SCOPUS:84862798557
SN - 0929-6646
VL - 111
SP - 67
EP - 76
JO - Journal of the Formosan Medical Association
JF - Journal of the Formosan Medical Association
IS - 2
ER -