NADPH-diaphorase reactivity in the ventral and dorsal lateral geniculate nuclei of rats

1992 ◽  
Vol 9 (2) ◽  
pp. 211-216 ◽  
Author(s):  
John Mitrofanis
Keyword(s):  
Lateral Geniculate Nucleus ◽  
Total Population ◽  
Ganglion Cells ◽  
Nadph Diaphorase ◽  
Dorsal Lateral Geniculate Nucleus ◽  
Small Cells ◽  
Double Labeling ◽  
Lateral Geniculate ◽  
Cell Class ◽  
Dorsal Lateral Geniculate

AbstractThe present study describes the patterns of NADPH-diaphorase reactivity in the ventral and dorsal lateral geniculate nuclei of rats. In the ventral lateral geniculate nucleus, two distinct populations of NADPH-diaphorase reactive cells are apparent. One population is deeply stained, generally larger in somal size and located in the more superficial or dorsolateral regions of the nucleus. The second population of reactive cells in the nucleus is lightly labeled, small in somal size, and found in deeper or more ventromedial regions of the nucleus. Double labeling with an antibody to GAB A revealed that neither cell class is GABAergic.In the dorsal lateral geniculate nucleus, reactivity is apparent in lightly labeled small cells only, most of which are GABA immunoreactive also. The NADPH-diaphorase reactive cells, however, form only a small proportion of the total population of GABAergic cells in the nucleus. The striking feature of the NADPH-diaphorase reactive cells in the dorsal lateral geniculate nucleus is their spatial distribution. Most cells are located in the more superficial or dorsolateral areas: very few are apparent in deeper or more ventromedial areas of the nucleus. This distribution closely parallels the location of the outer “shell” region of the nucleus (see Reese, 1988), which receives most of its afferents from the smaller class II and III ganglion cells of the retina and from the superior colliculus.

Selective expression and rapid regulation of GABAA receptor subunits in geniculocortical neurons of macaque dorsal lateral geniculate nucleus

1996 ◽  
Vol 13 (2) ◽  
pp. 223-235 ◽  
Author(s):  
Stewart H. C. Hendry ◽  
Karen L. Miller
Keyword(s):  
Lateral Geniculate Nucleus ◽  
Monocular Deprivation ◽  
Functional Adaptation ◽  
Dorsal Lateral Geniculate Nucleus ◽  
Double Labeling ◽  
Visual Activity ◽  
Inhibitory Neurotransmission ◽  
Lateral Geniculate ◽  
Inhibitory Mechanisms ◽  
Dorsal Lateral Geniculate

AbstractMonocular deprivation in adult macaques produces a rapid down-regulation in GABA and GABAA receptor subunit immunoreactivity in deprived-eye columns of primary visual cortex (V1) but a significantly delayed GABA reduction in deprived layers of the dorsal lateral geniculate nucleus (LGN). These findings, suggesting that normal inhibitory neurotransmission persists in LGN at a time when V1 inhibitory mechanisms are greatly altered, are consistent with physiological studies that have demonstrated a greater degree of functional plasticity in V1 than in LGN. Nonetheless, functional adaptation to partial loss of visual input has been detected in the LGN, indicating that synaptic plasticity takes place in this nucleus. In the present study, evidence for early changes in inhibitory neurotransmission were examined with immunocytochemical methods to determine if, in the absence of early GABA regulation, GABAA receptor subunits in macaque LGN are affected by adult deprivation. Immunoreactivity for α1 and β2/3 subunits of the GABAA receptor was intense within the magnocellular layers and more modest in the parvocellular layers and intercalated layers. In all layers, immunoreactivity was present in the cytoplasm and along the surfaces of relatively large somata and in dense tangles of processes in the neuropil. Double-labeling experiments demonstrated that somata and processes immunoreactive for α 1 and β2/3 were surrounded by GABA terminals but no cell intensely immunoreactive for either subunit expressed immunoreactivity for GABA, itself. Following periods of monocular deprivation by tetrodotoxin (TTX) injection for 4 days or longer, layers deprived of visual activity displayed levels of α 1 and β2/3 immunoreactivity markedly lower than those displayed by the adjacent, normally active layers. Such changes were greater as the period of deprivation increased. The changes included a loss of immunostaining in and around somata and in many neuropil elements of deprived layers. These data indicate that GABA and GABAA receptor subunits α 1 and β2/3 are expressed by separate populations of neurons in macaque LGN that are differentially regulated by visual activity. The findings suggest that rapid, activity-dependent regulation of postsynaptic receptors represents one mechanism for altering synaptic strength in the adult macaque visual system.

Effects of eliminating retinal Y cell input on center-surround interactions in the dorsal lateral geniculate nucleus of the cat

1996 ◽  
Vol 13 (6) ◽  
pp. 1089-1097 ◽  
Author(s):  
Chun Wang ◽  
B. Dreher ◽  
W. Burke
Keyword(s):  
Lateral Geniculate Nucleus ◽  
Ganglion Cells ◽  
Spot Size ◽  
Excitatory Input ◽  
Dorsal Lateral Geniculate Nucleus ◽  
Optimal Size ◽  
Lateral Geniculate ◽  
Optic Fibers ◽  
Dorsal Lateral Geniculate ◽  
Suppression Index

AbstractThe aim of this project was to investigate the interaction between Y retinal ganglion cells and the cells of the dorsal lateral geniculate nucleus (LGNd) of the cat, with particular reference to center-surround antagonism and intrageniculate inhibition. Responses of cells in the LGNd were studied by stimulating the retina with spots of light of constant contrast but varying size. The peak discharges of nonlagged X (XN) cells were strongly suppressed with increase in spot size but the responses of lagged X (XL) cells and nonlagged Y (YN) cells were inhibited much less strongly. The effect of the Y system on these responses was examined by producing a selective block of conduction in Y fibers in one optic nerve by means of a pressure cuff (Y-blocking). These effects were assessed by measuring the peak discharge rates and by calculation of a “peak suppression index.” Y-blocking had no significant effect on the peak suppression index of XL, cells in either lamina or on YN cells in the normal (not Y-blocked) lamina but had significant effects on the responses of XN cells, causing a decrease in peak suppression index, both for cells in laminae receiving their principal excitatory input from the Y-blocked eye (both lamina A and lamina A1 ) as well as those in lamina A (but not lamina A1 ) receiving their excitatory input from the normal eye. These effects were obtained with relatively large spots of light. Thus Y optic fibers have both intralaminar (monocular) and interlaminar (binocular) inhibitory effects on XN cells. In addition to these suppressive effects, the experiments also show that ipsilaterally projecting Y fibers have facilitatory effects on XN cells in lamina A when small spots of light, about optimal size for the XN cell, are used. These results suggest that the Y system plays a powerful role in shaping the responses of XN cells, possibly enhancing visual acuity.

Morphological diversity in terminals of W-type retinal ganglion cells at projection sites in cat brain

1996 ◽  
Vol 13 (3) ◽  
pp. 449-460 ◽  
Author(s):  
Boqing Chen ◽  
Xiao-Jiang Hu ◽  
Roberta G. Pourcho
Keyword(s):  
Lateral Geniculate Nucleus ◽  
Synaptic Vesicles ◽  
Ganglion Cells ◽  
Morphological Diversity ◽  
Dorsal Lateral Geniculate Nucleus ◽  
Anterograde Transport ◽  
Lateral Geniculate ◽  
Morphological Criteria ◽  
Cat Brain ◽  
Dorsal Lateral Geniculate

AbstractThe morphological features of retinal terminals in cat brain were examined at sites where projections of W-type ganglion cells predominate. These included the parvicellular C laminae of the dorsal lateral geniculate nucleus, the ventral lateral geniculate nucleus, stratum griseum superficiale of the superior colliculus, and the suprachiasmatic nucleus. Positive identification of retinal terminals was achieved following anterograde transport of intravitreally injected native or wheat germ agglutinin-conjugated horseradish peroxidase. In contrast to the classic features of retinal terminals as defined from sites where X- and Y-type ganglion cells predominate, i.e. round synaptic vesicles, large profiles, and pale mitochondria, substantial numbers of terminals in W-cell rich areas were found to contain dark mitochondria. Synaptic vesicles, although consistently round, were typically smaller in terminals with dark mitochondria than in those with pale mitochondria. These findings indicate a diversity among terminals of W-cells and suggest that such terminals cannot be distinguished on the basis of limited morphological criteria.

Transneuronal degeneration of beta retinal ganglion cells in the cat

1984 ◽  
Vol 222 (1226) ◽  
pp. 15-32 ◽  
Keyword(s):  
Visual Cortex ◽  
Retinal Ganglion Cells ◽  
Lateral Geniculate Nucleus ◽  
Ganglion Cells ◽  
Dendritic Morphology ◽  
Dorsal Lateral Geniculate Nucleus ◽  
Retinal Ganglion ◽  
Normal Numbers ◽  
Lateral Geniculate ◽  
Dorsal Lateral Geniculate

Transneuronal retrograde degeneration of retinal ganglion cells was investigated following neonatal visual cortex ablation in the cat. After a survival time of at least 18 months, retinal ganglion cells projecting to the thalamus were labelled by retrograde transport of horseradish peroxidase. Filled ganglion cells were classified into α , β and γ types on the basis of dendritic morphology. In normal cats, α cells made up 8-10% of the total population in the sample area, β cells made up 64-67% and γ cells made up 23-27%. In retinae of visual cortex-ablated cats, normal numbers of α and γ cells were present, but the β cell population was depleted by 90% of normal. Thalamic projections of surviving retinal ganglion cells were investigated by anterograde transport of tritiated proline injected into the eye. In these animals, ablation of visual cortex resulted in almost complete degeneration of laminae A and A1 of the dorsal lateral geniculate nucleus. In the radioautographic material, projections from the retina to the degenerated parts of laminae A and A1 were barely detectable. Survival of some ganglion cell populations and death of others after neonatal visual cortex ablation may be explained in terms of the pattern of projections of the different cell types. We conclude that the majority of β cells degenerate following visual cortex ablation because of removal of cells in the dorsal lateral geniculate nucleus which form their sole or principal target. Alpha and γ cells and 10% of β -cells survive because of extensive collateral projections to targets other than cells of the laminae A and A1 of dorsal lateral geniculate nucleus.

scholarly journals Not a one-trick pony: Diverse connectivity and functions of the rodent lateral geniculate complex

2017 ◽  
Vol 34 ◽  
Author(s):  
ABOOZAR MONAVARFESHANI ◽  
UBADAH SABBAGH ◽  
MICHAEL A. FOX
Keyword(s):  
Lateral Geniculate Nucleus ◽  
Ganglion Cells ◽  
Sensory Information ◽  
Dorsal Lateral Geniculate Nucleus ◽  
Projection Neurons ◽  
Retinal Ganglion ◽  
Unique Role ◽  
Visual Thalamus ◽  
Lateral Geniculate ◽  
Dorsal Lateral Geniculate

AbstractOften mislabeled as a simple relay of sensory information, the thalamus is a complicated structure with diverse functions. This diversity is exemplified by roles visual thalamus plays in processing and transmitting light-derived stimuli. Such light-derived signals are transmitted to the thalamus by retinal ganglion cells (RGCs), the sole projection neurons of the retina. Axons from RGCs innervate more than ten distinct nuclei within thalamus, including those of the lateral geniculate complex. Nuclei within the lateral geniculate complex of nocturnal rodents, which include the dorsal lateral geniculate nucleus (dLGN), ventral lateral geniculate nucleus (vLGN), and intergeniculate leaflet (IGL), are each densely innervated by retinal projections, yet, exhibit distinct cytoarchitecture and connectivity. These features suggest that each nucleus within this complex plays a unique role in processing and transmitting light-derived signals. Here, we review the diverse cytoarchitecture and connectivity of these nuclei in nocturnal rodents, in an effort to highlight roles for dLGN in vision and for vLGN and IGL in visuomotor, vestibular, ocular, and circadian function.

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