Advertisement

Springer Nature is making Coronavirus research free. View research | View latest news | Sign up for updates

Efferent neurons of the lateral-line system and the VIII cranial nerve in the brainstem of anurans

A comparative study using retrograde tracer methods

  • 55 Accesses

  • 30 Citations

Summary

The octavo-lateral efferent system of several anuran species was studied by means of retrograde transport of horseradish peroxidase. This system is organized similarly in all larval anurans and in all adult aglossids. All have two groups of efferent neurons in the nucleus reticularis medialis between the VIIIth and the IXth motor nucleus. The caudal group consists of efferent neurons that supply the posterior lateral-line nerve (NLLp) and a considerably smaller group of neurons supplying both the NLLp and the anterior lateral-line nerve (NLLa). The rostral group is composed of efferent neurons supplying the NLLa, neurons projecting to the inner ear and neurons supplying both the inner ear and the NLLa. Efferent neurons of the VIIIth cranial nerve exhibit a rostrocaudal cytoarchitectonic differentiation. Caudal perikarya, which are rounder in shape than those of the rostral part, have a dendritic projection to the superior olive. It is suggested that this differentiation reflects a functional differentiation of acoustic and vestibular efferent neurons.

Labeled neurons were ipsilateral to the site of application of HRP. None were found in the vestibular nuclei or in the cerebellum.

Efferent axons projecting to neuromasts of the NLLa leave the medulla with the VIIth nerve, axons projecting to neuromasts of the NLLp exit via the IXth nerve. Cell counts and the observation of axonal branching revealed that efferent units of both the lateral-line and the VIIIth-nerve system supply more than one receptor organ. In contrast to the lateral-line system, dendrites of efferent neurons of the VIIIth nerve project dorsally onto its nuclei, and afferents of the VIIIth nerve project onto efferent neurons. These structures most probably represent a feedback loop between the afferent and efferent systems of the VIIIth cranial nerve.

This is a preview of subscription content, log in to check access.

References

  1. Bell CC (1981) Central distribution of octavolateral afferents and efferents in a teleost (Mormyridae). J Comp Neurol 195:391–414

  2. Claas B, Münz H (1980) Bonyfish lateral line efferent neurons identified by retrograde axonal transport of horseradish peroxidase (HRP). Brain Res 193:249–253

  3. Claas B, Fritzsch B, Münz H (1981) Common efferents to lateral line and labyrinthine hair cells in aquatic vertebrates. Neurosci Lett 27:231–235

  4. Fritzsch B (1981a) The pattern of lateral-line afferents in urodeles. A horseradish-peroxidase study. Cell Tissue Res 218:581–594

  5. Fritzsch B (1981b) Efferent neurons to the labyrinth of Salamandra salamandra as revealed by retrograde transport of horseradish peroxidase. Neurosci Lett, in press

  6. Gacek RR, Lyron M (1974) The location of vestibular efferent neurons in the kitten with horseradish peroxidase. Acta Oto-Laryng 77:92–101

  7. Goldberg JM, Fernandez C (1980) Efferent vestibular system in the squirrel monkey: Anatomical location and influence on afferent activity. J Neurophys 43:986–1025

  8. Lowe DA, Russell IJ (1980) Central pathways of afferent and efferent fibers of the lateral line nerves in Xenopus. J Physiol 308:12P-13P

  9. Malmgren L, Olsson Y (1978) A sensitive method for histochemical demonstration of horseradish peroxidase in neurons following retrograde axonal transport. Brain Res 148:279–294

  10. Matesz C, Szekely G (1978) The motor column and sensory projections of the branchial cranial nerves in the frog. J Comp Neurol 178:157–176

  11. McCormick CA, Braford MR (1979) Identification of eighth efferent nerve cells in the bowfin Amia calva. Soc Neurosci Abstr 5:144

  12. Mensah P, Finger T (1975) Neuromelanine: a source of possible error in HRP material. Brain Res 98:183–188

  13. Nauta HJW, Pritz MB, Lasek RJ (1974) Afferents to the rat caudoputamen studied with horseradish peroxidase. Brain Res 67:219–238

  14. Nieuwkoop PD, Faber J (1967) Normal table of Xenopus laevis (Daudin). A systematical and chronological survey of the development. North-Holland Publishing Company, Amsterdam

  15. Plassmann W (1980) Central neuronal pathways in the lateral line system of Xenopus laevis. J Comp Physiol 136:203–213

  16. Precht W (1978) Neuronal operations in the vestibular system. In: Braitenberg V (ed) Studies of Brain Function. Springer Verlag, Berlin Heidelberg New York, Vol 2, pp 40–46

  17. Precht W, Richter A, Ozawa S, Shimazu H (1974) Intracellular study of frog's vestibular neurons in relation to the cerebellum and the spinal cord. Exp Brain Res 19:377–393

  18. Robbins RG, Bauknight RS, Honrubia V (1967) Anatomical distribution of efferent fibers in the VIIIth cranial nerve of the bullfrog (Rana catesbeiana). Acta Oto-Laryng 64:436–448

  19. Ross MD (1969) The general visceral efferent component of the eighth cranial nerve. J Comp Neurol 135:453–478

  20. Rubinson K, Friedman B (1977) Vagal afferent projection in Rana pipiens, Rana catesbeiana, and Xenopus mülleri. Brain Behav Evol 14:368–380

  21. Russell IJ (1976) Amphibian lateral line receptors. In: Llinas R, Precht W (eds) Frog neurobiology. Springer, Berlin Heidelberg New York, pp 513–550

  22. Schwarz IE, Schwarz DWF, Fredrickson JM, Landolt JP (1981) Efferent vestibular neurons: a study employing retrograde tracer methods in the pigeon (Columba livia). J Comp Neurol 196:1–12

  23. Shelton P (1970) The lateral line system at metamorphosis in Xenopus laevis. J Embryol Exp Morphol 24:511–524

  24. Strutz J (1981) The origin of centrifugal fibers to the inner ear in Caiman crocodilus. A horseradish peroxidase study. Neurosci Lett, in press

  25. Strutz J, Schmidt CL, Stürmer C (1980) Origin of efferent fibers of the vestibular apparatus in Goldfish. A horseradish peroxidase study. Neurosci Lett 18:5–9

  26. Strutz J, Spatz WB, Schmidt CL, Stürmer C (1981) Origin of centrifugal fibers to the labyrinth in the frog (Rana esculenta). A study with the fluorescent retrograde neuronal tracer “Fast blue”. Brain Res 215:323–328

  27. Szabo T, Libouban S (1979) On the course and origin of cranial nerves in the teleost fish Gnathonemus determined by ortho- and retrograde horseradish peroxidase axonal transport. Neurosci Lett 11:265–270

  28. Warr WB (1975) Olivocochlear and vestibular efferent neurons of the feline brain stem: Their location, morphology and number determined by retrograde transport and acetylcholinesterase histochemistry. J Comp Neurol 161:159–182

Download references

Author information

Correspondence to Udo Will.

Rights and permissions

Reprints and Permissions

About this article

Cite this article

Will, U. Efferent neurons of the lateral-line system and the VIII cranial nerve in the brainstem of anurans. Cell Tissue Res. 225, 673–685 (1982). https://doi.org/10.1007/BF00214812

Download citation

Key words

  • Lateral-line
  • Labyrinth
  • VIIIth cranial nerve
  • Efferent neurons
  • Anurans