Neuroscience 2003 Abstract
| Presentation Number: | 392.27 |
|---|---|
| Abstract Title: | Innervation of the striated muscular complex at the external urethral sphincter in the rat. |
| Authors: |
Pacheco, P.*1,2
; Martinez, A.2,3
; Alvarado, M.2
; Hernandez, M. E.2
; Manzo, J.2
1Inst. Inv Biomedicas, UNAM, Mexico City, Mexico 2Mexico, Apartado Postal 70228, 04510, 3Instituto de Neuroetologia, Apartado Postal 70228, 04510, |
| Primary Theme and Topics |
Motor Systems - Muscle and Motor Unit -- Anatomy |
| Secondary Theme and Topics | Cognition and Behavior<br />- Reproductive Behavior |
| Session: |
392. Muscle & Motor Unit: Function Poster |
| Presentation Time: | Monday, November 10, 2003 10:00 AM-11:00 AM |
| Location: | Morial Convention Center - Hall F-I, Board # I28 |
| Keywords: | MOTOR CONTROL, MUSCLE, NEUROMUSCULAR, REPRODUCTION |
The external urethral sphincter (EUS) has an important physiological interaction with the urinary bladder and reproductive glands during micturition and ejaculation. We described (SFN 667.12, 2002) that the EUS of male rats is a muscular complex of striated fibers compound of: the internal muscle of the prostatic segment of the urethra (1); the internal muscle of the membranous segment (2); the external muscle of the membranous segment (3); the anterior muscle of the membranous segment (4); the antero-lateral muscles of the EUS (5); and the postero-lateral muscles of the EUS (6). In this study we analyzed the supply of the pudendal nerve to those muscles. For this, unilateral anatomical dissections and electrical stimulation were made on the motor branch of the pudendal nerve (PN). Results: The first branch of the PN travels in direction to the bulbospongiosus muscle and external anal sphincter. After 3 mm it bifurcates innervating the ischiocavernosus and giving a branch with 3 ramifications to supply the EUS. One of these ramifications (branch I) travels to the prostatic segment and the others (branches II y III) travel to the muscles of the membranous segment of the urethra. The stimulation at low voltage of the motor branch produces contraction of muscle 1. When the voltage is increased, contractions of muscles 2, 3 and 4 are observed. After the additional transection of PN branch I, only the contraction of the muscle 1 of the EUS disappears. Conclusions: The motor branch of the PN participates, in each side of the animal, to the innervation of the EUS with independent branches to each muscle of the EUS muscular complex. This organization could account for a fine mechanic control for the expulsion of fluids during micturition and ejaculation.
Supported by CONACyT 164002 to MA and 33124-N to JM
Sample Citation:
[Authors]. [Abstract Title]. Program No. XXX.XX. 2003 Neuroscience Meeting Planner. New Orleans, LA: Society for Neuroscience, 2003. Online.
Copyright © 2003-2026 Society for Neuroscience; all rights reserved. Permission to republish any abstract or part of any abstract in any form must be obtained in writing by SfN office prior to publication.
