Cell Death In The Retina: Analysing The Switch That Triggers Dependency On Target-derived Trophic Factors
Funder
National Health and Medical Research Council
Funding Amount
$428,414.00
Summary
Construction of the developing nervous system in the embryo involves the creation of nerve cells and their connections, but also involves loss of a proportion of these cells prior to maturation. We will study this process of cell death and how developing nerve cells switch on their dependency to survival factors. In so doing we will better understand what happens when brain development goes wrong and also devise new ways to protect nerve cells in the injured or degenerate adult nervous system.
Glial-neuronal-vascular Interactions In A Novel Transgenic Model Of Muller Cell Dysfunction
Funder
National Health and Medical Research Council
Funding Amount
$626,585.00
Summary
Muller cell disfunction is a feature shared by many retinal diseases. This project aims to study the contribution of Muller cell dysfunction to retinal neuronal damage and blood-retinal barrier breakdown in a novel transgenic model we recently generated. Results of this study will also be of interest to scientists and clinicians seeking to understand better and treat diseases of the central nervous system in general.
The fovea is a specialized part of the retina which enables us to see fine detail. The fovea is characterised by an extremely high concentration of photoreceptor cells in a small, prescribed area to detect detail in the pattern of light reaching the retina. Each of these photoreceptor cells is connected to at least four other cells within the retina, which further refine the information coded by the photoreceptors. Because this circuitry involves so many cells, the retina has a tendency to be th ....The fovea is a specialized part of the retina which enables us to see fine detail. The fovea is characterised by an extremely high concentration of photoreceptor cells in a small, prescribed area to detect detail in the pattern of light reaching the retina. Each of these photoreceptor cells is connected to at least four other cells within the retina, which further refine the information coded by the photoreceptors. Because this circuitry involves so many cells, the retina has a tendency to be thick at the specialized area. However, in development the cells connected to the foveal photoreceptors move away from the central concentration of photoreceptors, still keeping their contacts with them. This results in thinning of the retina locally, so it has a volcanoe-like formation at the fovea, in which photoreceptors are concentrated within the crater and the displaced cells are accumulated on the rim. The events which trigger these cell displacements that form the fovea are unknown. We propose to investigate growth factors which signal between the fovea and the developing blood supply, and the relationship between the formation of the fovea and neuronal activity. This study will provide a new perspective on factors which affect central visual function and its vulnerability to insult in premature infants and in aging.Read moreRead less
How Does Glucose Protect The Retina And Optic Nerve Against Ischaemia?
Funder
National Health and Medical Research Council
Funding Amount
$418,171.00
Summary
Raised blood sugar levels are generally considered to be bad for nerve cells, especially those in the eye. But we have made a groundbreaking discovery finding that in the short-term, sugar can rescue nerve cells in the eye from death caused by lack of blood flow. In this project we will investigate how this remarkable effect is achieved.
INTRARETINAL OXYGEN CONSUMPTION AND THE PREVENTION OF HYPOXIA IN RETINAL ISCHEMIA
Funder
National Health and Medical Research Council
Funding Amount
$164,444.00
Summary
Adequate oxygen supply to the retina is critical for normal visual function. The oxygen is normally supplied by the blood flowing in the two circulations that support the retina. These are the choroidal circulation, lying behind the retina, and the retinal circulation, which supports the front half of the retina. The retinal circulation is particularly vulnerable to vascular disease and insufficient blood flow (ischemia). Vascular changes are involved in a wide range of retinal diseases which ar ....Adequate oxygen supply to the retina is critical for normal visual function. The oxygen is normally supplied by the blood flowing in the two circulations that support the retina. These are the choroidal circulation, lying behind the retina, and the retinal circulation, which supports the front half of the retina. The retinal circulation is particularly vulnerable to vascular disease and insufficient blood flow (ischemia). Vascular changes are involved in a wide range of retinal diseases which are currently responsible for the majority of new blindness in our community. The choroidal circulation is relatively robust, and offers a potential avenue for increasing oxygen delivery to the retina in the clinical management of ischemic retinal diseases. The feasibility of such an approach is strongly dependent on the oxygen requirements of the retina, and how this is influenced by retinal ischemia. We plan to find out how much oxygen is consumed by the many different layers within the retina under normal conditions and then determine how this changes under ischemic conditions. We will then see if we can supply enough oxygen from the choroid by a combination of raising the oxygen content of the blood, increasing choroidal blood flow, and reducing the amount of oxygen used by the outer half of the retina. Our experiments will be done in laboratory rats, but the same principles are readily transferable to humans if they prove to be beneficial in protecting the retina from ischemic damage. Our study will also quantify the relationship between oxygen levels in the blood stream, and those in the different layers of the retina. This information may prove valuable in the treatment and the prevention of other retinal diseases where the manipulation of the intraretinal oxygen environment is an exciting new avenue of research.Read moreRead less
The Role Of Ten-m3 In Patterning Ipsilateral Retinal Projections
Funder
National Health and Medical Research Council
Funding Amount
$453,042.00
Summary
The normal functioning of the brain depends on connections of billions of nerve cells or neurons. We have found that a protein called Ten_m3 plays a very important role in specifying the way that neurons from the eye connect to the brain. The role of this protein is so important that mice which lack the protein behave as if they are blind. The aim of this project is to understand how this protein controls the development of the visual system.