Nucleus raphe obscurus (nRO) regulation of anorectal motility in rats

Gregory Holmes, J. M. Martau, G. E. Hermann, R. C. Rogers, J. C. Bresnahan, M. S. Beattie

Research output: Contribution to journalArticle

12 Citations (Scopus)

Abstract

Previous research has demonstrated that anorectal contractions in the rat are modulated by activation of spinal autonomic circuits. In the present study, anterograde tracing of descending pathways originating from the caudal nucleus raphe obscures (nRO) revealed that this nucleus projects to cells within the intermediolateral (IML) cell column of the thoracic cord and the sacral parasympathetic nucleus (SPN). These anatomical studies suggested that the nRO may influence the regulation of spinal reflexes of the pelvic floor. In a second set of experiments, acute rat preparations were used to investigate changes in anorectal motility during electrical stimulation of the nRO. Anorectal contractions were measured by a fluid-filled manometer. Electrical stimulation of the nRO significantly reduced spontaneous anorectal activity when compared to baseline contractions recorded for 1 min prior to stimulation. Stimulation sites outside the nRO did not affect anorectal contractions when compared to either (a) the l-min pre-stimulation baseline for that site or (b) the l-min stimulation period for sites within the nRO. Stimulation of caudal portions of the nRO were more likely than the rostral nRO to reduce anorectal contractions. Given that the SPN contains preganglionic neurons which may be involved in control of anorectal contractions (mediated via the pelvic nerve), the studies presented here suggest a functional role for nRO regulation of preganglionic motoneurons innervating the distal gut of the rat.

Original languageEnglish (US)
Pages (from-to)197-204
Number of pages8
JournalBrain research
Volume759
Issue number2
DOIs
StatePublished - Jun 6 1997

Fingerprint

Electric Stimulation
Pelvic Floor
Raphe Nuclei
Nucleus Raphe Obscurus
Motor Neurons
Reflex
Spinal Cord
Neurons
Research
Spinal Cord Lateral Horn

All Science Journal Classification (ASJC) codes

  • Neuroscience(all)
  • Molecular Biology
  • Clinical Neurology
  • Developmental Biology

Cite this

Holmes, G., Martau, J. M., Hermann, G. E., Rogers, R. C., Bresnahan, J. C., & Beattie, M. S. (1997). Nucleus raphe obscurus (nRO) regulation of anorectal motility in rats. Brain research, 759(2), 197-204. https://doi.org/10.1016/S0006-8993(97)00249-7
Holmes, Gregory ; Martau, J. M. ; Hermann, G. E. ; Rogers, R. C. ; Bresnahan, J. C. ; Beattie, M. S. / Nucleus raphe obscurus (nRO) regulation of anorectal motility in rats. In: Brain research. 1997 ; Vol. 759, No. 2. pp. 197-204.
@article{31960dc429f1497cad4a670cc70ee9db,
title = "Nucleus raphe obscurus (nRO) regulation of anorectal motility in rats",
abstract = "Previous research has demonstrated that anorectal contractions in the rat are modulated by activation of spinal autonomic circuits. In the present study, anterograde tracing of descending pathways originating from the caudal nucleus raphe obscures (nRO) revealed that this nucleus projects to cells within the intermediolateral (IML) cell column of the thoracic cord and the sacral parasympathetic nucleus (SPN). These anatomical studies suggested that the nRO may influence the regulation of spinal reflexes of the pelvic floor. In a second set of experiments, acute rat preparations were used to investigate changes in anorectal motility during electrical stimulation of the nRO. Anorectal contractions were measured by a fluid-filled manometer. Electrical stimulation of the nRO significantly reduced spontaneous anorectal activity when compared to baseline contractions recorded for 1 min prior to stimulation. Stimulation sites outside the nRO did not affect anorectal contractions when compared to either (a) the l-min pre-stimulation baseline for that site or (b) the l-min stimulation period for sites within the nRO. Stimulation of caudal portions of the nRO were more likely than the rostral nRO to reduce anorectal contractions. Given that the SPN contains preganglionic neurons which may be involved in control of anorectal contractions (mediated via the pelvic nerve), the studies presented here suggest a functional role for nRO regulation of preganglionic motoneurons innervating the distal gut of the rat.",
author = "Gregory Holmes and Martau, {J. M.} and Hermann, {G. E.} and Rogers, {R. C.} and Bresnahan, {J. C.} and Beattie, {M. S.}",
year = "1997",
month = "6",
day = "6",
doi = "10.1016/S0006-8993(97)00249-7",
language = "English (US)",
volume = "759",
pages = "197--204",
journal = "Brain Research",
issn = "0006-8993",
publisher = "Elsevier",
number = "2",

}

Holmes, G, Martau, JM, Hermann, GE, Rogers, RC, Bresnahan, JC & Beattie, MS 1997, 'Nucleus raphe obscurus (nRO) regulation of anorectal motility in rats', Brain research, vol. 759, no. 2, pp. 197-204. https://doi.org/10.1016/S0006-8993(97)00249-7

Nucleus raphe obscurus (nRO) regulation of anorectal motility in rats. / Holmes, Gregory; Martau, J. M.; Hermann, G. E.; Rogers, R. C.; Bresnahan, J. C.; Beattie, M. S.

In: Brain research, Vol. 759, No. 2, 06.06.1997, p. 197-204.

Research output: Contribution to journalArticle

TY - JOUR

T1 - Nucleus raphe obscurus (nRO) regulation of anorectal motility in rats

AU - Holmes, Gregory

AU - Martau, J. M.

AU - Hermann, G. E.

AU - Rogers, R. C.

AU - Bresnahan, J. C.

AU - Beattie, M. S.

PY - 1997/6/6

Y1 - 1997/6/6

N2 - Previous research has demonstrated that anorectal contractions in the rat are modulated by activation of spinal autonomic circuits. In the present study, anterograde tracing of descending pathways originating from the caudal nucleus raphe obscures (nRO) revealed that this nucleus projects to cells within the intermediolateral (IML) cell column of the thoracic cord and the sacral parasympathetic nucleus (SPN). These anatomical studies suggested that the nRO may influence the regulation of spinal reflexes of the pelvic floor. In a second set of experiments, acute rat preparations were used to investigate changes in anorectal motility during electrical stimulation of the nRO. Anorectal contractions were measured by a fluid-filled manometer. Electrical stimulation of the nRO significantly reduced spontaneous anorectal activity when compared to baseline contractions recorded for 1 min prior to stimulation. Stimulation sites outside the nRO did not affect anorectal contractions when compared to either (a) the l-min pre-stimulation baseline for that site or (b) the l-min stimulation period for sites within the nRO. Stimulation of caudal portions of the nRO were more likely than the rostral nRO to reduce anorectal contractions. Given that the SPN contains preganglionic neurons which may be involved in control of anorectal contractions (mediated via the pelvic nerve), the studies presented here suggest a functional role for nRO regulation of preganglionic motoneurons innervating the distal gut of the rat.

AB - Previous research has demonstrated that anorectal contractions in the rat are modulated by activation of spinal autonomic circuits. In the present study, anterograde tracing of descending pathways originating from the caudal nucleus raphe obscures (nRO) revealed that this nucleus projects to cells within the intermediolateral (IML) cell column of the thoracic cord and the sacral parasympathetic nucleus (SPN). These anatomical studies suggested that the nRO may influence the regulation of spinal reflexes of the pelvic floor. In a second set of experiments, acute rat preparations were used to investigate changes in anorectal motility during electrical stimulation of the nRO. Anorectal contractions were measured by a fluid-filled manometer. Electrical stimulation of the nRO significantly reduced spontaneous anorectal activity when compared to baseline contractions recorded for 1 min prior to stimulation. Stimulation sites outside the nRO did not affect anorectal contractions when compared to either (a) the l-min pre-stimulation baseline for that site or (b) the l-min stimulation period for sites within the nRO. Stimulation of caudal portions of the nRO were more likely than the rostral nRO to reduce anorectal contractions. Given that the SPN contains preganglionic neurons which may be involved in control of anorectal contractions (mediated via the pelvic nerve), the studies presented here suggest a functional role for nRO regulation of preganglionic motoneurons innervating the distal gut of the rat.

UR - http://www.scopus.com/inward/record.url?scp=0030790279&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0030790279&partnerID=8YFLogxK

U2 - 10.1016/S0006-8993(97)00249-7

DO - 10.1016/S0006-8993(97)00249-7

M3 - Article

VL - 759

SP - 197

EP - 204

JO - Brain Research

JF - Brain Research

SN - 0006-8993

IS - 2

ER -

Holmes G, Martau JM, Hermann GE, Rogers RC, Bresnahan JC, Beattie MS. Nucleus raphe obscurus (nRO) regulation of anorectal motility in rats. Brain research. 1997 Jun 6;759(2):197-204. https://doi.org/10.1016/S0006-8993(97)00249-7