Summary
The cat dorsal lateral geniculate nucleus (LGN) was examined at the light- and electron-microscopic level after immunocytochemistry for GAD (the synthesizing enzyme of the inhibitory neurotransmitter GABA), to identify cells and processes with GAD-like immunoreactivity. GAD-positive perikarya were distributed throughout the A and C laminae, constituting a moderate proportion of cells in the LGN. Labeled cells were characterized by small size, scant cytoplasm, relatively large nuclei with common indentations, small mitochondria, few organelles and few strands of rough endoplasmic reticulum. Unlabeled cells were of large, medium and small size. GAD-positive terminals were identified as F1 and F2 types (Guillery's nomenclature) on the basis of their synaptic relations and ultrastructure. Labeled F2 terminals were postsynaptic to retinal (RLP) boutons and presynaptic to unlabeled dendrites in synaptic glomeruli. Labeled F1 terminals made synapses on unlabeled somata and dendrites, and on labeled dendrites and F2 terminals. Presumably, most labeled F1 terminals originate from GABAergic perigeniculate axons. Retinal (RLP) and cortico-geniculate (RSD) boutons remained unlabeled in the reative zone. These terminals made synapses with labeled and unlabeled dendrites and with labeled F2 boutons. In conjunction with previous studies on GAD-positive cells in the perigeniculate nucleus, these results provide immunocytochemical and morphological evidence suggesting that the GABAergic intrinsic and extrinsic (perigeniculate) interneurons mediate the different inhibitory phenomena which occur in relay cells of the cat LGN. The ultrastructural features and synaptic relations of GABAergic cells and processes in the cat LGN are similar to those of equivalent neural elements in the LGN of rat and monkey, suggesting general principles of organization and morphology for GABAergic neurons in the thalamus of different mammals.
Similar content being viewed by others
References
Ahlsén G, Lindström S (1978a) Axonal branching of functionally identified neurones in the lateral geniculate body of the cat. Neurosci Lett Suppl 1: S156
Ahlsén G, Lindström S (1978b) Projection of perigeniculate neurons to the lateral geniculate body in the cat. Neurosci Lett Suppl 1: S367
Ahlsén G, Lindström S (1982) Excitation of perigeniculate neurones via axon collaterals of principal cells. Brain Res 236: 477–481
Ahlsén G, Lindström S, Sybirska E (1978) Subcortical axon collaterals of principal cells. Brain Res 236: 477–481
Colonnier M (1968) Synaptic patterns on different cell types in the different laminae of the cat visual cortex. An electron microscope study. Brain Res 9: 268–287
Curtis DR, Tebecis AK (1972) Bicuculline and thalamic inhibition. Exp Brain Res 16: 210–218
de Lima AD, Montero VM, Singer W (1984) The cholinergic innervation in the dorsal lateral geniculate and perigeniculate nucleus of the cat. An EM-immunocytochemical study. Soc Neurosci Abstr 10: 55
de Lima AD, Montero VM, Singer W (1985) The cholinergic innervation of the visual thalamus: an EM immunocytochemical study. Exp Brain Res (in press)
Dubin MW, Cleland BG (1977) Organization of visual inputs to interneurons of lateral geniculate nucleus of the cat. J Neurophysiol 40: 410–427
Famiglietti EV, Peters A (1972) The synaptic glomerulus and the intrinsic neuron in the dorsal lateral geniculate nucleus of the cat. J Comp Neurol 144: 285–334
Fitzpatrick D, Penny GR, Schmechel DE (1984) Glutamic acid decarboxylase-immunoreactive neurons and terminals in the lateral geniculate nucleus of the cat. J Neurosci 4: 1809–1829
Friedländer MJ, Lin CS, Stanford LR, Sherman SM (1981) Morphology of functionally identified neurons in lateral geniculate nucleus of the cat. J Neurophysiol 46: 80–129
Geisert EE (1980) Cortical projections of the lateral geniculate nucleus in the cat. J Comp Neurol 190: 793–812
Guillery RW (1966) A study of Golgi preparations from the dorsal lateral geniculate nucleus of the adult cat. J Comp Neurol 128: 21–50
Hámori J, Pasik P, Pasik T (1983) Differential frequency of P-cells and I-cells in magnocellular and parvocellular laminae of monkey lateral geniculate nucleus. An ultrastructural study. Exp Brain Res 52: 57–66
Hendrickson AE, Ogren MP, Vaughn JE, Barber RP, Wu JY (1983) Light and electron microscopic immunocytochemical localization of glutamic acid decarboxylase in monkey geniculate complex: evidence for GABAergic neurons and synapses. Neuroscience 3: 1245–1262
Ide LS (1982) The fine structure of the perigeniculate nucleus in the cat. J Comp Neurol 210: 317–334
Karlsson U (1966) Three-dimensional studies of neurons in the lateral geniculate nucleus of the rat. II. Environment of perikarya and proximal parts of their branches. J Ultrastruct Res 16: 482–504
LeVay S, Ferster D (1977) Relay cell classes in the lateral geniculate nucleus of the cat and the effects of visual deprivation. J Comp Neurol 172: 563–584
LeVay S, Ferster D (1979) Proportion of interneurons in the cat's lateral geniculate nucleus. Brain Res 164: 304–308
Lieberman AR, Webster KE (1974) Aspects of the synaptic organization of intrinsic neurons in the dorsal lateral geniculate nucleus. An ultrastructural study of the normal and of the experimentally deafferented nucleus in the rat. J Neurocytol 3: 677–710
Lin CS, Kratz KE, Sherman SM (1977) Percentage of relay cells in the cat's lateral geniculate nucleus. Brain Res 131: 167–173
Lindström S (1982) Synaptic organization of inhibitory pathways to principal cells in the lateral geniculate nucleus of the cat. Brain Res 234: 447–453
Lindström S (1983) Interneurones in the lateral geniculate nucleus with monosynaptic excitation from retinal ganglion cells. Acta Physiol Scand 119: 101–103
Montero VM, Scott GL (1981) Synaptic terminals in the dorsal lateral geniculate nucleus from neurons of the thalamic reticular nucleus: a light and electron microscope autoradiographic study. Neuroscience 6: 2561–2577
Montero VM, Singer W (1984a) Ultrastructure and synaptic relations of neural elements containing glutamic acid decarboxylase (GAD) in the perigeniculate nucleus of the cat: a light and electron microscopic immunocytochemical study. Exp Brain Res 56: 115–125
Montero VM, Singer W (1984b) Ultrastructure and synaptic relations of glutamic acid decarboxylase (GAD)-immunoreactive neural elements in the dorsal lateral geniculate nucleus of the cat. Soc Neurosci Abstr 10: 55
Morgan R, Sillito AM, Woltencroft JH (1974) A pharmacological investigation of inhibition in the lateral geniculate nucleus. J Physiol (Lond) 246: 93–94
Ohara PT, Lieberman AR, Hunt SP, Wu JY (1983) Neural elements containing glutamic acid decarboxilase (GAD) in the dorsal lateral geniculate nucleus of the rat; immunohistochemical studies by light and electron microscopy. Neuroscience 8: 189–211
Peters A, Palay SL, Webster HF (1970) The fine structure of the nervous system. The cells and their processes. Harper and Row, New York
Robson JA (1983) The morphology of corticofugal axons to the dorsal lateral geniculate nucleus in the cat. J Comp Neurol 216: 89–103
Saito K, Wu JY, Roberts E (1974) Immunochemical comparison of vertebrate glutamic acid decarboxylase. Brain Res 65: 277–285
Sanderson KJ (1971) The projection of the visual field to the lateral geniculate and medial interlaminar nuclei in the cat. J Comp Neurol 143: 101–118
Sillito AM, Kemp JA (1983) The influence of GABAergic inhibitory processes on the receptive field structure of X and Y cells in cat dorsal lateral geniculate nucleus (dLGN). Brain Res 277: 63–78
Singer W (1977) Control of thalamic transmission by corticofugal and ascending reticular pathways in the visual system. Physiol Rev 57: 386–420
Singer W, Bedworth N (1973) Inhibitory interaction between X and Y units in the cat lateral geniculate nucleus. Brain Res 49: 291–307
Sterling P, Davis TL (1980) Neurons in cat lateral geniculate nucleus that concentrate exogenous [3H]-γ-aminobutyric acid (GABA). J Comp Neurol 192: 737–749
Szentágothai J, Hámori J, Tömböl T (1966) Degeneration and electron microscope analysis of the synaptic glomeruli in the lateral geniculate body. Exp Brain Res 2: 283–301
Weber AJ, Kalil RE (1983) The percentage of interneurons in the dorsal lateral geniculate nucleus of the cat and observations on several variables that affect the sensitivity of horseradish peroxidase as a retrograde marker. J Comp Neurol 220: 336–346
Wilson JR, Friedländer MJ, Sherman SM (1984) Fine structural morphology of identified X- and Y-cells in the cat's lateral geniculate nucleus. Proc R Soc 221: 411–436
Wu JY, Lin CT, Brandon C, Chan TS, Mohler H, Richards JG (1982) Regulation and immunocytochemical characterization of glutamic acid decarboxylase. In: Chan-Palay V, Palay SL (eds) Cytochemical methods in neuroanatomy. Alan R Liss Inc. New York, pp 279–296
Wu JY, Matsuda T, Roberts E (1973) Purification and characterization of glutamate decarboxylase from mouse brain. J Biol Chem 248: 3029–3934
Zucker C, Yazulla S, Wu JY (1984) Non-correspondence of [3H]GABA uptake and GAD localization in goldfish amacrine cells. Brain Res 298: 154–158
Author information
Authors and Affiliations
Additional information
Supported in part by grants EY 02877 and HD 03352 from the National Institutes of Health
Rights and permissions
About this article
Cite this article
Montero, V.M., Singer, W. Ultrastructural identification of somata and neural processes immunoreactive to antibodies against glutamic acid decarboxylase (GAD) in the dorsal lateral geniculate nucleus of the cat. Exp Brain Res 59, 151–165 (1985). https://doi.org/10.1007/BF00237675
Received:
Accepted:
Issue Date:
DOI: https://doi.org/10.1007/BF00237675