Summary
The taste buds of the circumvallate papillae have been examined by electron microscopy in OsO4-fixed, PTA stained material or after KMnO4 fixation. The microvilli of the receptor cells have terminal dilatations which presumably give an increased surface area for transduction. The extracellular spaces at the necks of the receptor cells near the bases of the microvilli are interrupted by closed contacts.
The synapses have a well defined synaptic cleft suggesting a chemical rather than an electrical mode of transmission. Synaptic membrane specialisations differ from the membrane “thickenings” of other types of synapse. Presynaptic “dense projections” are present but there is no well define postsynaptic “thickening”. Vesicles occur in both pre- and postsynaptic components, but it is debatable whether or not they should be termed “synaptic vesicles”.
This is a preview of subscription content, log in via an institution to check access.
Similar content being viewed by others
References
Beidler, L. M.: Dynamics of taste cells. In: Olfaction and Taste (ed. Y. Zotterman), p. 133–144. London: Pergamon Press 1963.
De Lorenzo, A. J.: Electron microscopic observations on the taste buds of the rabbit. J. biophys. biochem. Cytol. 4, 143–150 (1958).
— Studies on the ultrastructure and histophysiology of cell membranes, nerve fibres and synaptic junctions in chemoreceptors. In: Olfaction and Taste (ed. Y. Zotterman), p. 5–17. London: Pergamon Press 1963.
Duncan, C. J.: Excitatory mechanisms in chemo- and mechanoreceptors. J. theor. Biol. 5, 114–126 (1963a).
— Synaptic transmission at taste buds. Nature (Lond.) 203, 875–876 (1963b).
— The transducer mechanism of sense organs. Naturwissenschaften 7, 172–173 (1964).
Elfvin, L. G.: Electron microscopic investigation of filament structures in unmyelinated fibres of cat splenic nerve. J. Ultrastruct. Res. 5, 51–64 (1961).
Engström, H., and C. Rytzner: The fine structure of taste buds and taste fibres. Ann. Otol. (St. Louis) 65, 1–15 (1956).
Flock, A.: Electron microscopic and electro-physiological studies on the lateral line canal organ. Acta Otolaryngol. Suppl., 199, 1–90 (1965).
Gray, E. G.: Axo-somatic and axo-dendritic synapses of the cerebral cortex: an electron microscope study. J. Anat. (Lond.) 93, 420–433 (1959).
— The granule cells, mossy synapses and Purkinje spine synapses of the cerebellum: light and electron microscope observations. J. Anat. (Lond.) 95, 345–356 (1961).
- Electron microscopy of synaptic organelles of the central nervous system. In: Proc. IV. Int. Congr. Neuropath. (Ed. H. Jacob) 2, 57–61 (1962).
— Electron microscopy of presynaptic organelles of the spinal cord. J. Anat. (Lond.) 97, 101–106 (1963).
— Tissues of the central nervous system. In: Electron Microscopic Anatomy (Ed. S. M. Kurtz), p. 369–417. New York: Academic Press 1964a.
— Electron microscopy of the cell surface. Endeavour 23, 61–65 (1964b).
- Problems of interpreting the fine structure of vertebrate and invertebrate synapses. In: Int. Rev. Gen. and exp. Zool. (in press) (1965).
— and R. W. Guillery: An electron microscope study of the ventral nerve cord of the leech. Z. Zellforsch. 60, 826–849 (1963).
- - Synaptic morphology in normal and degenerating nervous system. Int. Rev. Cytol. (in press) (1965).
Katz, B.: The transmission of impulses from nerve to muscle, and the subcellular unit of synaptic action. Proc. roy. Soc. B 155, 455–477 (1962).
Mullinger, A. M.: The fine structure of ampullary electric receptors in Amiurus. Proc. Roy. Soc. B. 160, 345–59 (1964).
Murray, R. G., and A. Murray: The fine structure of the taste buds of Rhesus and Cynomalgus monkeys. Anat. Rec. 138, 211–233 (1960).
Nemetschek-Gansler, H., u. H. Ferner: Über die Ultrastruktur der Geschmacksknospen. Z. Zellforsch. 63, 155–178 (1964).
Palay, S. L.: Synapses in the central nervous system. J. biophys. biochem. Cytol., Suppl. 2, 193–202 (1956).
Ranvier, L. A.: Traité technique d'Histologie, 2nd edit. Paris 1889.
Robertson, J. D.: The ultrastructure of cell membranes and their derivatives. Biochem. Soc. Symp. 16, 3–43 (1959).
Trujillo-Cenóz, O.: Electron microscope study of the rabbit gustatory bud. Z. Zellforsch. 46, 272–280 (1957).
Westrum, L. E.: On the origin of synaptic vesicles in the cerebral cortex. J. Physiol. P. in Press (1965).
Yamamoto, T.: On the thickness of the unit membrane. J. Cell. Biol. 17, 413–422 (1963).
Author information
Authors and Affiliations
Additional information
Acknowledgements. We are indebted to Professor J. Z. Young, F. R. S., for his stimulating support, and to Mr. S. Waterman for skilled photography.
Rights and permissions
About this article
Cite this article
Gray, E.G., Watkins, K.C. Electron microscopy of taste buds of the rat. Z.Zellforsch 66, 583–595 (1965). https://doi.org/10.1007/BF00368248
Received:
Issue Date:
DOI: https://doi.org/10.1007/BF00368248