Developmental loss of functional laminin receptors on retinal ganglion cells is regulated by their target tissue, the optic tectum

Development ◽  
1989 ◽  
Vol 107 (2) ◽  
pp. 381-387 ◽  
Author(s):  
J. Cohen ◽  
V. Nurcombe ◽  
P. Jeffrey ◽  
D. Edgar

The ability of chick retinal ganglion cells (RGCs) to extend neurites on tissue culture substrata of the extra-cellular matrix protein laminin is lost during embryonic development. In order to establish the mechanism responsible for the loss of response, the number of high affinity (KD 10(−9) M) laminin receptors on both the cell bodies and neurites of RGCs were determined throughout this period by a ligand binding assay using radio-labelled laminin. It was found that the loss of response paralleled a decrease in receptor numbers on both the cell bodies and the neurites of the RGCs. Bilateral tectal ablation at embryonic day 6 resulted in the subsequent maintenance of laminin-stimulated neurite outgrowth, together with a partial inhibition of the loss of laminin receptors. Thus, the loss of response of the RGCs to laminin reflects a decrease in the numbers of laminin receptors on these neurons, and furthermore, this down-regulation is in turn dependent on innervation of the target tissue.

Development ◽  
1980 ◽  
Vol 55 (1) ◽  
pp. 77-92
Author(s):  
S. C. Sharma ◽  
J. G. Hollyfield

The specification of central connexions of retinal ganglion cells was studied in Xenopus laevis. In one series of experiments, the right eye primordium was rotated 180° at embryonic stages 24–32. In the other series, the left eye was transplanted into the right orbit, and vice versa, with either 0° or 180° rotation. After metamorphosis the visual projections from the operated eye to the contralateral optic tectum were mapped electrophysiologically and compared with the normal retinotectal map. In all cases the visual projection map was rotated through the same angle as was indicated by the position of the choroidal fissure. The left eye exchanged into the right orbit retained its original axes and projected to the contralateral tectum. These results suggest that retinal ganglion cell connexions are specified before stage 24.


1992 ◽  
Vol 9 (3-4) ◽  
pp. 389-398 ◽  
Author(s):  
Luiz R. G. Britto ◽  
Dȃnia E. Hamassaki-Britto

AbstractA small number of enkephalin-like immunoreactive cells were observed in the ganglion cell layer of the pigeon retina. Many of these neurons were identified as ganglion cells, since they were retrogradely labeled after injections of fluorescent latex microspheres in the contralateral optic tectum. These ganglion cells were mainly distributed in the inferior retina, and their soma sizes ranged from 12–26 μm in the largest axis. The enkephalin-containing ganglion cells appear to represent only a very small percentage of the ganglion cells projecting to the optic tectum (less than 0.1%). Two to 7 weeks after removal of the neural retina, there was an almost complete elimination of an enkephalin-like immunoreactive plexus in layer 3 of the contralateral, rostrodorsal optic tectum. These data provide evidence for the existence of a population of enkephalinergic retinal ganglion cells with projections to the optic tectum.


1988 ◽  
Vol 1 (1) ◽  
pp. 73-81 ◽  
Author(s):  
Rodrigo O. Kuljis ◽  
Harvey J. Karten

AbstractRecent immunocytochemical studies indicate the existence of several classes of peptide- (PRGC) and catecholamine-containing retinal ganglion cells in anurans, birds, and mammals. Different classes of PRGC project to discrete and seemingly unique layers in the retino-recipient portion of the anuran and avian optic tectum. Peptide-containing retinofugal projections to the frog tectum originate early in development, and are reestablished by some classes of PRGC during regeneration of the optic nerve. These findings indicate that chemically specific, parallel retinofugal pathways presumably subserve different functional aspects of vision in vertebrates. Exciting prospects for research include the correlation of physiologically with immunocytochemically defined classes of retinal ganglion cells, the analysis of the possible role of neuroactive peptides in retinofugal transmission, and the pharmacological manipulation of putative peptidergic retinofugal pathways to analyze their role in visual function.


2002 ◽  
Vol 19 (5) ◽  
pp. 575-581 ◽  
Author(s):  
ALINO MARTINEZ-MARCOS ◽  
ENRIQUE LANUZA ◽  
FERNANDO MARTINEZ-GARCIA

Retinal ganglion cells projecting to the optic tectum and visual thalamus have been investigated in the lizard, Podarcis hispanica. Injections of biotinylated dextran-amine in the optic tectum reveal seven morphological cell varieties including one displaced ganglion cell type. Injections in the visual thalamus yield similar ganglion cell classes plus four giant ganglion cells, including two displaced ganglion cell types. The present study constitutes the first comparison of tectal versus thalamic ganglion cell types in reptiles. The situation found in lizards is similar to that reported in mammals and birds where some cell types projecting to the thalamus are larger than those projecting to the mesencephalic roof. The presence of giant retino-thalamic ganglion cells with specific dendritic arborizations in sublaminae A and B of the inner plexiform layer suggests that parts of the visual thalamus of lizards could be implicated in movement detection, a role that might be played by the ventral lateral geniculate nucleus, which is involved in our tracer injections.


2015 ◽  
Vol 2015 ◽  
pp. 1-8 ◽  
Author(s):  
Jin Wook Jeoung ◽  
Minhong Jeun ◽  
Joo Hyun Park ◽  
Yu Jeong Kim ◽  
Seongtae Bae ◽  
...  

Background. Magnetic hyperthermia using superparamagnetic nanoparticle (SPNP) agents is considered a promising biotechnological approach to induce heat shock proteins (HSPs) in a target tissue because it can generate accurately controllable localized heating.Objectives. The main objective of this study is to demonstrate induction of HSPs in cultured retinal ganglion cells (RGCs) by using engineered Mn0.5Zn0.5Fe2O4SPNP agents coated with polyethylene glycol (PEG) 500.Methods. The Mn0.5Zn0.5Fe2O4nanoparticles were synthesized using a high temperature thermal decomposition method. The AC heating characteristics of PEG 500-coated Mn0.5Zn0.5Fe2O4nanoparticles were investigated using an AC solenoid coil-capacitor system.Results. PEG 500-coated SPNPs efficiently penetrated into the cytoplasm of RGCs without causing obvious cytological changes and showed stable and well-saturated self-heating temperature rise characteristics. Immunofluorescent staining images showed that AC magnetic hyperthermia successfully induced HSP72 in RGCs incubated with Mn0.5Zn0.5Fe2O4nanoparticles. In Western blot analysis, a significant increase in immunoreactivity was observed for RGCs incubated with SPNPs in a fixed AC magnetic field (fappl=140 kHz andHappl=140 Oe).Conclusion. Our results demonstrate that the induction of HSP72 with a magnetic nanofluid hyperthermia could potentially be used as a neuroprotective treatment modality by way of enhancing a natural cytoprotective response.


1989 ◽  
Vol 3 (5) ◽  
pp. 477-482 ◽  
Author(s):  
Luiz R. G. Britto ◽  
Kent T. Keyser ◽  
Dania E. Hamassaki ◽  
Toru Shimizu ◽  
Harvey J. Karten

AbstractImmunohistochemical and retrograde tracing techniques were combined to study the retinal ganglion cells which project to the pars ventralis of the lateral geniculate nucleus (GLv) in the pigeon. Using two different fluorescent tracers, two histochemically-distinct populations of ganglion cells were found to project to both the GLv and the optic tectum. The first population of ganglion cells exhibited tyrosine hydroxylase-like immunoreactivity and represented about 20% of all ganglion cells which were retrogradely labeled from the GLv. The second population of ganglion cells showed substance P-like immunoreactivity and represented about 13% of all ganglion cells projecting to the GLv. These results confirm earlier suggestions that the retinal axons projecting to the GLv also project elsewhere and demonstrate that heterogeneity of retinal ganglion cells transmitters is evident even within a single retino-recipient nucleus such as the GLv.


1976 ◽  
Vol 192 (1108) ◽  
pp. 331-352 ◽  

At the same developmental stage at which a photoreceptor potential can first be recorded in the chicken’s retina a visually evoked response can be elicited in its optic tectum. Retina and optic tectum, therefore, seem to start functioning simultaneously. This paper discusses experimental investigations into how the various components of the chicken visual system develop. The investigation was carried out in three steps. With morphological techniques the growth and differentiation processes of retinal ganglion cells compared to that of receptor cells were observed and a quantitative study of the development of optic nerve fibres was made. With physiological techniques the functional properties of retinal ganglion cells and their axons were tested at successive stages of development. A correlation between the morphogenesis and the physiogenesis of this system was then carried out. A model to explain the growth in fibre diameter with time was constructed. The relation between conduction velocity and fibre diameter was studied and was found to be different from that in the adult. For myelinated fibres a theoretical explanation for the relationship in the developing chicken could be found, and it could also be shown that as time progresses such a relationship passes over to that found in the adult. The final link in the construction of the chain of elements forming the visual system was found to be the late maturation of the receptor outer segments in the retina.


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