title: Influence of serotonergic mechanisms on the urine flow rate in male rats.
abstract: This study extensively examined the role of a 5-HT(1A) receptor in controlling voiding function in anesthetized male rats. A simultaneous recording of the intravesical pressure (IVP), external urethral sphincter (EUS)-electromyography (EMG), and urine flow rate (UFR) during continuous cystometry was used. 8-Hydroxy-2-(di-n-propylamino)-tetralin (8-OH-DPAT), a 5-HT(1A) receptor agonist, significantly improved the voiding efficiency, as detected by increases in the evoked contraction amplitude, EUS burst period, and silent period, and decreases in the volume threshold, pressure threshold, and residual volume. Interestingly, the UFR during voiding was reduced by 8-OH-DPAT, as evidenced by decreases in the maximal UFR and mean UFRs of the voiding period, spike duration, and interspike interval. Conversely, treating rats with WAY-100635, a 5-HT(1A) antagonist, produced effects opposite to those produced by 8-OH-DPAT. These findings suggest that 8-OH-DPAT improved the voiding efficiency by enhancing the detrusor contractile ability and prolonging EUS burst period, which would compensate for the lower UFR, resulting from urethral smooth muscle contractions and longer EUS silent periods during voiding. The present study contributes to our understanding of the role of 5-HT(1A) receptors in controlling the urine flow rate in male rats.
authors.affiliation: Department and Institute of Physiology, National Yang-Ming University, Taipei, Taiwan; Department of Physical Medicine and Rehabilitation, School of Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan;
authors.forename: Wen-Jia
authors.initials: WJ
authors.lastname: Fan
authors.affiliation: Department of Physical Medicine and Rehabilitation, School of Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan; Department of Physical Medicine and Rehabilitation, Taipei Medical University Hospital, Taipei, Taiwan;
authors.forename: Shih-Ching
authors.initials: SC
authors.lastname: Chen
authors.affiliation: Graduate Institute of Neural Regenerative Medicine, Taipei Medical University, Taipei, Taiwan; Center for Neurotrauma and Neuroregeneration, Taipei Medical University, Taipei, Taiwan;
authors.forename: Tsung-Hsun
authors.initials: TH
authors.lastname: Hsieh
authors.affiliation: Department of Physical Medicine and Rehabilitation, School of Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan; Department of Physical Medicine and Rehabilitation, Taipei Medical University Hospital, Taipei, Taiwan;
authors.forename: Chien-Hung
authors.initials: CH
authors.lastname: Lai
authors.affiliation: Department of Physiology, School of Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan; and.
authors.forename: You Shuei
authors.initials: YS
authors.lastname: Lin
authors.affiliation: Department of Physical Medicine and Rehabilitation, School of Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan; Department of Physical Medicine and Rehabilitation, Taipei Medical University Hospital, Taipei, Taiwan; Neuroscience Research Center, Taipei Medical University Hospital, Taipei, Taiwan.
authors.forename: Chih-Wei
authors.initials: CW
authors.lastname: Peng
authors.affiliation: Department and Institute of Physiology, National Yang-Ming University, Taipei, Taiwan; yrkou@ym.edu.tw.
authors.forename: Yu Ru
authors.initials: YR
authors.lastname: Kou
mesh_terms: D000818:Animals; D004576:Electromyography; D008297:Male; D011312:Pressure; D017207:Rats, Sprague-Dawley; D044282:Receptor, Serotonin, 5-HT1A / Q000187:drug effects / Q000378:metabolism*; D012701:Serotonin / Q000378:metabolism*; D058825:Serotonin 5-HT1 Receptor Agonists / Q000494:pharmacology; D058829:Serotonin 5-HT1 Receptor Antagonists / Q000494:pharmacology; D012737:Sex Factors; D015398:Signal Transduction; D013997:Time Factors; D014521:Urethra / Q000187:drug effects / Q000378:metabolism*; D001743:Urinary Bladder / Q000187:drug effects / Q000378:metabolism*; D014554:Urination / Q000187:drug effects; D014563:Urodynamics / Q000187:drug effects
chemical_list: D058825:Serotonin 5-HT1 Receptor Agonists; D058829:Serotonin 5-HT1 Receptor Antagonists; D044282:Receptor, Serotonin, 5-HT1A; D012701:Serotonin
keywords: 8-hydroxy-2-(di-n-propylamino)-tetralin; WAY-100635; external urethral sphincter-electromyography; intravesical pressure; voiding efficiency