Summary
The organization of posterior and anterior afferents of the lateralline system was studied in several species of urodeles by means of transganglionic transport of horseradish peroxidase. The afferents of each lateral-line nerve form distinct fascicles in the medullary alar plate. Each of the two branches of the anterior lateral-line nerve is organized in two long and one short fascicles. The posterior lateral-line afferents form only two long fascicles. Each ordinary neuromast is supplied by only two afferents, which run in the two ventral medullary fiber bundles. It is suggested that afferents to hair cells displaying one type of polarity form together one bundle, but those contacting hair cells polarized in the opposite way form the second ventral bundle of one lateral-line branch. Thus, the lateral-line afferents may be organized in a directotopic fashion.
The short dorsal fascicle formed only by the anterior lateral-line afferents receives fibers exclusively from small pit organs. Each pit organ is supplied by only one afferent. Anatomically, these pit organs resemble in many respects the electroreceptive ampullary organs of certain fish.
Neurons labeled retrogradely via the anterior lateral-line nerve afferents have been attributed to the nervus trigeminus or facialis. In addition to the posterior lateral-line afferents, only few centrifugally projecting neurons were labeled. These neurons are discussed as efferents to the posterior lateral-line neuromasts.
Similar content being viewed by others
Reference
Adams JC (1977) Technical considerations on the use of horseradish peroxidase as a neuronal marker. Neuroscience 2:141–145
Bell CC, Russell CJ (1978) Termination of electroreceptor and mechanical lateral line afferents in the mormyrid acoustico-lateral area. J Comp Neurol 182:367–382
Bodznick D, Northcutt RG (1980) Segregation of electro- and mechanoreceptive inputs to the elasmobranch medulla. Brain Res 195:313–321
Bodznick D, Northcutt RG (1981) Electroreception in lampreys: Evidence that the earliest vertebrates were electroreceptive. Science 212:465–467
Boord RL, Campbell CBG (1977) Structural and functional organization of the lateral line system of sharks. Am Zool 17:431–443
Boord RL, Eisworth LM (1972) The central terminal fields of posterior lateral line and eight nerves of Xenopus. Am Zool 12:722
Chezar HH (1930) Studies on the lateral-line system of Amphibia. II. Comparative cytology and innervation of lateral line organs in the Urodela. J Comp Neurol 50:159–175
Claas B, Münz H (1980) Bonyfish lateral line efferent neurons identified by retrograde axonal transport of horseradish peroxidase (HRP). Brain Res 193:249–253
Escher K (1925) Das Verhalten der Seitenorgane der Wirbeltiere und ihrer Nerven beim Übergang zum Landleben. Acta Zool, Stockh 6:307–414
Flock A (1971) The lateral line organ mechanoreceptors. In: Hoar WS, Randall DJ (eds) Fish physiology, V. Academic Press, New York, p 241–264
Fritzsch B (1980) Metamorphotic changes in the arrangement of vestibular and lateral line afferents in the medulla of Salamandra salamandra. Neurosci Lett Suppl 5:423
Görner P (1963) Untersuchungen zur Morphologie und Elektrophysiologie des Seitenlinienorgans des Krallenfrosches (Xenopus laevis Daudin). Z vergl Physiol 47:316–338
Goldberg JM, Fernández C (1980) Efferent vestibular system in the squirrel monkey: Anatomical location and influence on afferent activity. J Neurophys 43:986–1025
Grant G, Arvidson J, Robertson B, Ygge J (1979) Transganglionic transport of horseradish peroxidase in primary sensory neurons. Neurosci Lett 12:23–28
Herrick CJ (1948) The Brain of the Tiger Salamander Ambystoma tigrinum. University of Chicago Press, Chicago London
Hetherington TE, Wake MH (1979) The lateral line system in larval Ichthyophis (Amphibia: Gymnophiona). Zoomorphol 93:209–225
Kingsbury BF (1895) The lateral line system of sense organs in some American Amphibia, and comparison with the dipnoans. Trans Am Micr Soc 17:115–146
Koester DM, Boord RL (1978) The central projections of first order anterior lateral line neurons of the clearnose skate, Raja eglanteria. Am Zool 18:587
Lowe DA, Russell IJ (1980) Central pathways of afferent and efferent fibers of lateral line nerves in Xenopus, J Physiol 308:12P-13P
Malbranc M (1876) Von der Seitenlinie und ihren Sinnesorganen bei Amphibien. Zeitsch f Wiss Zool 26:24–86
Maler L, Finger T, Karten HJ (1974) Differential projections of ordinary lateral line receptors and electroreceptors in the gymnotid fish, Apternotus (Sternarchus) albifrom. J Comp Neurol 158:363–382
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
Matesz C (1979) Central projection of the VIIIth cranial nerve in the frog. Neuroscience 4:2061–2071
Mesulam M-M (1976) The blue reaction in horseradish peroxidase neurohistochemistry: Incubation parameters and visibility. J Histochem Cytochem 24:1273–1280
Northcutt RG (1980) Central auditory pathways in anamniotic vertebrates. In: Popper AN, Fay R (eds) Comparative studies of hearing in vertebrates, Springer-Verlag, New York, p 79–118
Opdam P, Nieuwenhuys R (1976) Topological analysis of the brain stem of the axolotl Ambystoma mexicanum. J Comp Neurol 165:285–306
Plassmann W (1980) Central neuronal pathways in the lateral line system of Xenopus laevis. J Comp Physiol 136:203–213
Roth A, Tscharntke H (1976) Ultrastructure of the ampullary electroreceptors in lungfish and Brachiopterygii. Cell Tissue Res 173:95–108
Russell IJ (1976) Amphibian lateral line receptors. In: Llinás R, Precht W (eds) Frog neurobiology. A Handbook. Springer-Verlag, Berlin Heidelberg New York, p 513–550
Strutz J, Spatz WB (1980) Superior olivary and extraolivary origin of centrifugal innervation of the cochlea in guinea pig. A horseradish peroxidase study. Neurosci Lett 17:227–230
Szabo T (1974) Anatomy of the specialized lateral line organs of electroreception. In: Fessard A (ed) Handbook of sensory physiology. Vol III, 3. Electroreceptors and other specialized receptors in lower vertebrates. Springer-Verlag, Berlin Heidelberg New York, p 13–58
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
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Fritzsch, B. The pattern of lateral-line afferents in urodeles. Cell Tissue Res. 218, 581–594 (1981). https://doi.org/10.1007/BF00210117
Accepted:
Issue Date:
DOI: https://doi.org/10.1007/BF00210117