Summary
Synapses of optic nerve afferents (optic synapses) in the rat suprachiasmatic nucleus (SCN) have been identified ultrastructurally. They are easily distinguished from other types of synapses. The optic boutons are characterized by the presence of large mitochondria with a swollen electron lucent matrix and an interconnected tubular system formed by their inner membrane. Other, more variable features include: 1) a scattered pattern of synaptic vesicles which are found throughout the entire presynaptic element with relatively little accumulation near the active zones; 2) the occurrence of dense core vesicles and glycogen granules; 3) the active zones, the majority of which is Gray-type I, but a minority can obviously be classified as Gray's type II; 4) the innervation of smaller peripheral dendrites and dendritic spines. Boutons of this kind are exclusively filled with anterogradely transported horseradish peroxidase injected into both eyes. Very few neuronal elements containing the typical mitochondria have been observed in the SCN on the 6th day post partum, increasingly more on the 9th and 12th day, but considerably higher numbers after opening of the eyes on the 17th and the following days. The location of normal and degenerating optic boutons was examined light- and electron microscopically. In the rostral third of the SCN there are relatively few optic synapses which are found close to the optic chiasma. In the middle portion of the SCN optic synapses increase in number; they are found not only in the ventral part of the nucleus but also in lateral regions. This becomes particularly obvious in the caudal third of the SCN.
Article PDF
Similar content being viewed by others
Avoid common mistakes on your manuscript.
References
Akert, K., Pfenninger, K., Sandri, C., Moor, H.: Freeze etching and cytochemistry of vesicles and membrane complexes in synapses of the central nervous system. In: Structure and function of synapses (G.D. Pappas and D.P. Purpura, eds.), pp. 67–86. New York: Raven Press 1972
Birks, R.J., Mackey, M.C., Weldon, P.R.: Organelle formation from pinocytotic elements in neurites of cultured sympathetic ganglia. J. Neurocytol. 1, 311–340 (1972)
Bodian, D.: An electron microscopic characterization of classes of synaptic vesicles by means of controlled aldehyde fixation. J. Cell Biol. 44, 115–124 (1970)
Brauer, K., Winkelmann, E.: Quantitative Charakterisierung der afferenten Axone in der pars dorsalis des corpus geniculatum laterale (Cgld) der Albinoratte an Golgi-Präparaten. Z. mikr.-anat. Forsch. 88, 1110–1124 (1974)
Cleland, B.G., Levick, W.R.: Brisk and sluggish concentrically organized ganglion cells in the cat's retina. J. Physiol. (Lond.) 240, 421–456 (1974a)
Cleland, B.G., Levick, W.R.: Properties of rarely encountered types of ganglion cells in the cat's retina and an overall classification. J. Physiol. (Lond.) 240, 457–492 (1974)
Colman, D.R., Scalia, F., Cabrales, E.: Light and electron microscopic observations on the anterograde transport of horseradish peroxidase in the optic pathway in the mouse and rat. Brain Res. 102, 156–163 (1976)
Conrad, C.D., Stumpf, W.E.: Endocrine-optic pathways to the hypothalamus. Anatomical Neuroendocrinology. Int. Conf. Neurobiology of CNS-Hormone Interactions, Chapel Hill, 1974, pp. 15–29. Basel: Karger 1975
Cullen, M.J., Kaiserman-Abramof, J.R.: Cytological organization of the dorsal lateral geniculate nuclei in mutant anophthalmic and postnatally enucleated mice. J. Neurocytol. 5, 407–424 (1976)
Felong, M.: Development of the retino-hypothalamic projection in the rat. Anat. Rec. 184, 400–401 (1976)
Fukuda, Y., Stone, J.A.: Retinal distribution and central projections of Y-, X-, and W-cells of the cat's retina. J. Neurophysiol. 37, 749–772 (1974)
Gray, E.G.: Axo-somatic and axo-dendritic synapses of the cerebral cortex: An electron microscope study. J. Anat. (Lond.) 93, 420–433 (1959)
Green, D.E., Asai, J., Harris, R.A., Penniston, J.T.: Conformational basis of energy transformations in membrane systems. III Configurational changes in the mitochondrial inner membrane induced by changes in functional states. Arch. Biochem. Biophys. 125, 684–705 (1968)
Güldner, F.-H.: Synaptology of the rat suprachiasmatic nucleus. Cell Tiss. Res. 165, 509–544 (1976)
Güldner, F.-H.: Synapses of optic nerve afferents in the rat suprachiasmatic nucleus. II. Structural variability as revealed by morphometric examination. Cell Tiss. Res. 194, 37–54 (1978)
Güldner, F.-H., Wolff, J.R.: Dendro-dendritic synapses in the suprachiasmatic nucleus of the rat hypothalamus. J. Neurocytol. 3, 245–250 (1974)
Güldner, F.-H., Wolff, J.R.: Prinzipien der komplexen Synapsenanordnung (KSA) am Beispiel des N. suprachiasmaticus (SCN). Verh. anat. Ges. 71, 925–926 (1977)
Güldner, F.-H., Wolff, J.R.: Retinal afferents form Gray-type-I and type-II synapses in the suprachiasmatic nucleus (rat). Exp. Brain Res. 32, 83–90 (1978a)
Güldner, F.-H., Wolff, J.R.: Self-innervation of dendrites in the rat suprachiasmatic nucleus. Exp. Brain Res. 32, 77–82 (1978b)
Hartwig, H.G.: Electron microscopic evidence for a retinohypothalamic projection to the suprachiasmatic nucleus of Passer domesticus. Cell Tiss. Res. 153, 89–99 (1974)
Hayes, B.P., Webster, K.E.: An electron microscope study of the retino-receptive layers of the pigeon optic tectum. J. comp. Neurol. 162, 447–466 (1975)
Hendrickson, A.E., Wagoner, N., Cowan, W.M.: An autoradiographic and electron microscopic study of retino-hypothalamic connections. Z. Zellforsch. 135, 1–26 (1972)
Jones, D.G.: Synapses and synaptosomes. Morphological aspects. London: Chapman and Hall 1975
Kelly, J.P., Gilbert, C.D.: The projections of different morphological types of ganglion cells in the cat retina. J. comp. Neurol. 163, 65–80 (1975)
Krisch, B.: Immunohistochemical and electron microscopic study of the rat hypothalamic nuclei and cell clusters under various experimental conditions. Cell Tiss. Res. 174, 109–127 (1976)
Laufer, M., Vanegas, H.: The optic tectum of a perciform teleost II. Fine structure. J. comp. Neurol. 154, 61–96 (1974)
Lenn, N.J., Beebe, B., Moore, R.Y.: Postnatal development of the suprachiasmatic hypothalamic nucleus of the rat. Cell Tiss. Res. 178, 463–475 (1977)
Le Vay, S.: On the neurons and synapses of the lateral geniculate nucleus of the monkey, and the effects of eye enucleation. Z. Zellforsch. 113, 396–419 (1971)
Lund, R.D.: Synaptic patterns of the superficial layers of the superior colliculus of the rat. J. comp. Neurol. 135, 179–208 (1969)
Lund, R.D., Lund, J.S.: Development of synaptic patterns in the superior colliculus of the rat. Brain Res. 42, 1–20 (1972)
Lund, J.S., Lund, R.D.: The effects of varying periods of visual deprivation on synaptogenesis in the superior colliculus of the rat. Brain Res. 42, 21–32 (1972)
Mai, J.: Quantitative autoradiographische Untersuchungen am subcorticalen optischen System der Albinoratte. Dissertation, Medizinische Fakultät, Universität Düsseldorf (1976)
Mai, J.K., Junger, E.: Quantitative autoradiographic light- and electron microscopic studies on the retino-hypothalamic connections in the rat. Cell Tiss. Res. 183, 221–238 (1977)
McMahan, U.J.: Fine structure of synapses in the dorsal nucleus of the lateral geniculate body of normal and blinded rats. Z. Zellforsch. 76, 116–146 (1967)
Mason, C.A.: Delineation of the rat visual system by the axonal iontophoresis-cobalt sulfide precipitation technique. Brain Res. 85, 287–293 (1975)
Mason, C.A., Lincoln, D.W.: Visualization of the retino-hypothalamic projection in the rat cobalt precipitation. Cell Tiss. Res. 168, 117–131 (1976)
Mason, C.A., Sparrow, N., Lincoln, D.W.: Structural features of the retinohypothalamic projection in the rat during normal development. Brain Res. 132, 141–148 (1977)
Milhaud, M., Pappas, G.D.: The fine structure of neurons and synapses of the habenula of the cat with special reference to the subjunctional bodies. Brain Res. 3, 158–173 (1966)
Millhouse, O.E.: Optic chiasm collaterals afferent to the suprachiasmatic nucleus. Brain Res. 137, 351–355 (1977)
Moore, R.Y.: Retinohypothalamic projection in mammals: a comparative study. Brain Res. 49, 403–409 (1973)
Moore, R.Y., Lenn, N.J.: A retinohypothalamic projection in the rat. J. comp. Neurol. 146, 1–74 (1972)
Nishino, H., Koizumi, K., Brooks, C.M.: The role of the suprachiasmatic nuclei of the hypothalamus in the production of circadian rhythm. Brain Res. 112, 45–59 (1976)
Quatacker, J.: Endocytosis and multivesicular body formation in rabbit luteal cells during pseudopregnancy. Cell Tiss. Res. 161, 541–553 (1975)
Répérant, J., Angaut, P.: The retinotectal projections in the pigeon. An experimental optical and electron microscopic study. Neuroscience 2, 119–140 (1977)
Reynolds, E.S.: The use of lead citrate at high pH as an electron-opaque stain in electron microscopy. J. Cell Biol. 17, 208–213 (1963)
Sterling, P.: Quantitative mapping with the electron microscope: retinal terminals in the superior colliculus. Brain Res. 54, 347–354 (1973)
Szentágothai, J., Hámori, J., Tömböl, T.: Degeneration and electron microscope analysis of the synaptic glomeruli in the lateral geniculate body. Exp. Brain Res. 2, 283–301 (1966)
Thorpe, P.A.: The presence of a retino-hypothalamic projection in the ferret. Brain Res. 85, 343–346 (1975)
Tigges, J., O'Steen, W.K.: Termination of retinofugal fibers in squirrel monkey: a re-investigation using autoradiographic methods. Brain Res. 79, 489–495 (1974)
Valdivia, O.: Methods of fixation and the morphology of synaptic vesicles. Anat. Rec. 166, 392 (1970)
Valverde, F.: The neuropil in superficial layers of the superior colliculus of the mouse. Z. Anat. Entwickl.-Gesch. 142, 117–147 (1973)
Vandesande, F., Dierickx, K., De Mey, J.: Identification of the vasopressin-neurophysin producing neurons of the rat suprachiasmatic nuclei. Cell Tiss. Res. 156, 377–380 (1975)
Van Harreveld, A., Trubatch, J., Steiner, J.: Rapid freezing and electron microscopy for the arrest of physiological processes. J. Microscopy 100, 189–198 (1974)
Weldon, P.R.: Pinocytotic uptake and intracellular distribution of colloidal thorium dioxide by cultured sensory neurites. J. Neurocytol. 4, 341–356 (1975)
Wenisch, H.J.C.: Retino-hypothalamic projection in the mouse: Electron microscopic and iontophoretic investigations of hypothalamic and optic centers. Cell Tiss. Res. 167, 547–561 (1976)
Winkelmann, E., Brauer, K., Marx, J., David, H.: Elektronenmikroskopische und lichtmikroskopische Untersuchungen optischer und kortikaler Afferenzen im Corpus geniculatum laterale, pars dorsalis der Albinoratte unter besonderer Berücksichtigung der synaptischen Organisation. J. Hirnforsch. 17, 305–333 (1976)
Yamada, H.: Light and electron microscopic analysis of the medial terminal nucleus of the accessory optic system in the mouse. Z. mikr.-anat. Forsch. 88, 997–1017 (1974)
Author information
Authors and Affiliations
Additional information
The author wishes to thank Mrs. Bassirat Pirouzmandi for her excellent technical assistance
Rights and permissions
About this article
Cite this article
Güldner, F.H. Synapses of optic nerve afferents in the rat suprachiasmatic nucleus. Cell Tissue Res. 194, 17–35 (1978). https://doi.org/10.1007/BF00209231
Accepted:
Issue Date:
DOI: https://doi.org/10.1007/BF00209231