Skip to main content
PMC home page
The Journal of Physiology logoLink to The Journal of Physiology
. 1971 Dec;219(3):587–610. doi: 10.1113/jphysiol.1971.sp009679

The locations and activities of medullary neurones associated with ruminant forestomach motility

R Harding, B F Leek
PMCID: PMC1331650  PMID: 5157594

Abstract

1. Neuronal activity bearing a temporal relationship with spontaneous reticulo-ruminal movements was recorded with micro-electrodes from the medulla oblongata in halothane-anaesthetized sheep. Recording sites were located histologically after causing electro-coagulation at the micro-electrode tip.

2. One hundred and forty-four gastric units were recorded from the dorsal vagal nucleus and up to 1 mm dorsal and lateral to the nucleus between transverse planes 1 mm caudal, and 4 mm rostral, to the obex. It is considered that records were obtained from the regions of cell bodies.

3. The discharges of thirty-two vagal preganglionic motoneurones were identified by an antidromic collision technique. Conduction velocities ranged from 10-26 m/sec. They were located in the dorsal vagal nucleus and up to 0·5 mm dorsal and lateral to the nucleus. The majority of motoneurones innervated either the reticulum or the rumen. One ruminal unit discharged during both primary and secondary cycle movements.

4. One hundred and twelve units which were not orthodromically or antidromically activated by stimulating the vagus nerves were considered to be interneurones. Four types were distinguishable on the basis of their patterns of discharge during primary cycle movements.

5. The discharges of Type A interneurones resembled those of gastric motoneurones, having no resting discharge between contraction cycles. Their discharges were temporally related to either reticular contractions or rumen contractions during primary and secondary cycle movements.

6. Types B and C interneurones have resting discharges which, respectively, increased and either decreased or stopped during each primary cycle movement.

7. Discharges of only three units identified as interneurones resembled the discharges of gastric vagal afferent units.

Full text

PDF

Selected References

These references are in PubMed. This may not be the complete list of references from this article.

  1. ANDERSSON B., KITCHELL R. L., PERSSON N. A study of central regulation of rumination and reticulo-ruminal motility. Acta Physiol Scand. 1959 Aug 31;46:319–338. doi: 10.1111/j.1748-1716.1959.tb01762.x. [DOI] [PubMed] [Google Scholar]
  2. BEGHELLI V., BORGATTI G., MAVRULIS A., PARMEGGIANI P. L. SULLA ORGANIZZAZIONE DEL CENTRO RIFLESSO DEL RETICOLO NELL'OVINO. Arch Sci Biol (Bologna) 1964 Jul-Sep;48:249–266. [PubMed] [Google Scholar]
  3. BEGHELLI V., BORGATTI G., PARMEGGIANI P. L. ON THE ROLE OF THE DORSAL NUCLEUS OF THE VAGUS IN THE REFLEX ACTIVITY OF THE RETICULUM. Arch Ital Biol. 1963 Oct 5;101:365–384. [PubMed] [Google Scholar]
  4. BELL F. R., LAWN A. M. Localization of regions in the medulla oblongata of sheep associated with rumination. J Physiol. 1955 Jun 28;128(3):577–592. doi: 10.1113/jphysiol.1955.sp005326. [DOI] [PMC free article] [PubMed] [Google Scholar]
  5. BELL F. R. The localization within the dorsal motor nucleus of the vagus of the efferent fibres to the ruminant stomach. J Anat. 1960 Jul;94:410–417. [PMC free article] [PubMed] [Google Scholar]
  6. Beghelli V., Harding R., Leek B. F. Do the gastric centres need an excitatory input? J Physiol. 1971 Jul;216(2):75P–76P. [PubMed] [Google Scholar]
  7. Beghelli V., Mavrulis A. Attività unitaria del nucleo dorsale del vago motilità riflessa atrio-ruminale, nell'ovino. Arch Sci Biol (Bologna) 1966 Oct-Dec;50(4):296–306. [PubMed] [Google Scholar]
  8. DUNCAN D. L. The effects of vagotomy and splanchnotomy on gastric motility in the sheep. J Physiol. 1953 Feb 27;119(2-3):157–169. doi: 10.1113/jphysiol.1953.sp004836. [DOI] [PMC free article] [PubMed] [Google Scholar]
  9. HABEL R. E. A study of the innervation of the ruminant stomach. Cornell Vet. 1956 Oct;46(4):555–633. [PubMed] [Google Scholar]
  10. Harding R., Leek B. F. The location of gastric motor units in the medulla of sheep. J Physiol. 1971;214 (Suppl):39P–40P. [PubMed] [Google Scholar]
  11. Howard B. R. The dorsal nucleus of the vagus as a centre controlling gastric motility in sheep. J Physiol. 1970 Jan;206(1):167–180. doi: 10.1113/jphysiol.1970.sp009004. [DOI] [PMC free article] [PubMed] [Google Scholar]
  12. IGGO A. Central nervous control of gastric movements in sheep and goats. J Physiol. 1956 Jan 27;131(1):248–256. doi: 10.1113/jphysiol.1956.sp005460. [DOI] [PMC free article] [PubMed] [Google Scholar]
  13. IGGO A. Spontaneous and reflexly elicited contractions of reticulum and rumen in decerebrate sheep. J Physiol. 1951 Dec 28;115(4):74–P. [PubMed] [Google Scholar]
  14. IGGO A. Tension receptors in the stomach and the urinary bladder. J Physiol. 1955 Jun 28;128(3):593–607. doi: 10.1113/jphysiol.1955.sp005327. [DOI] [PMC free article] [PubMed] [Google Scholar]
  15. IGGO A. The electrophysiological identification of single nerve fibres, with particular reference to the slowest-conducting vagal afferent fibres in the cat. J Physiol. 1958 Jun 18;142(1):110–126. doi: 10.1113/jphysiol.1958.sp006002. [DOI] [PMC free article] [PubMed] [Google Scholar]
  16. Iggo A., Leek B. F. An electrophysiological study of single vagal efferent units associated with gastric movements in sheep. J Physiol. 1967 Jul;191(1):177–204. doi: 10.1113/jphysiol.1967.sp008244. [DOI] [PMC free article] [PubMed] [Google Scholar]
  17. Iggo A., Leek B. F. An electrophysiological study of some reticulo-ruminal and abomasal reflexes in sheep. J Physiol. 1967 Nov;193(1):95–119. doi: 10.1113/jphysiol.1967.sp008345. [DOI] [PMC free article] [PubMed] [Google Scholar]
  18. Kerr F. W. Preserved vagal visceromotor function following destruction of the dorsal motor nucleus. J Physiol. 1969 Jun;202(3):755–769. doi: 10.1113/jphysiol.1969.sp008839. [DOI] [PMC free article] [PubMed] [Google Scholar]
  19. Leek B. F. Reticulo-ruminal function and dysfunction. Vet Rec. 1969 Mar 8;84(10):238–243. doi: 10.1136/vr.84.10.238. [DOI] [PubMed] [Google Scholar]
  20. Leek B. F. Reticulo-ruminal mechanoreceptors in sheep. J Physiol. 1969 Jun;202(3):585–609. doi: 10.1113/jphysiol.1969.sp008829. [DOI] [PMC free article] [PubMed] [Google Scholar]
  21. Lewis P. R., Scott J. A., Navaratnam V. Localization in the dorsal motor nucleus of the vagus in the rat. J Anat. 1970 Sep;107(Pt 2):197–208. [PMC free article] [PubMed] [Google Scholar]
  22. MITCHELL G. A., WARWICK R. The dorsal vagal nucleus. Acta Anat (Basel) 1955;25(2-4):371–395. doi: 10.1159/000141082. [DOI] [PubMed] [Google Scholar]
  23. SZABO T., DUSSARDIER M. LES NOYAUX D'ORIGINE DU NERF VAGUE CHEZ LE MOUTON. Z Zellforsch Mikrosk Anat. 1964 Jul 6;63:247–276. [PubMed] [Google Scholar]
  24. Sellers A. F., Stevens C. E. Motor functions of the ruminant forestomach. Physiol Rev. 1966 Oct;46(4):634–661. doi: 10.1152/physrev.1966.46.4.634. [DOI] [PubMed] [Google Scholar]

Articles from The Journal of Physiology are provided here courtesy of The Physiological Society

RESOURCES