Rat Models of Diabetic Retinal Neurodegeneration in the MICRON Literature

About the MICRON Research Literature

These research pages organize published studies using MICRON imaging systems by animal species and the disease or condition investigated.

All publication counts and figures reflect the complete indexed research collection.

Explore related studies through the MICRON Research Hubs or search the complete publication collection in the reSEARCH portal.

Understanding Diabetic Retinal Neurodegeneration

Diabetic retinal neurodegeneration names a set of neural and glial changes reported in the diabetic retina:

• Thinning of the inner retinal layers
• Loss of retinal ganglion cells
• Muller cell gliosis
• Functional deficits that appear as reduced oscillatory potentials and a reduced photopic negative response

Whether these changes are an early stage of diabetic retinopathy or a process running alongside it is argued both ways in the literature and is not settled here. What both readings share is that neural change can be detected before, or without, the vascular lesions by which retinopathy is graded in the clinic.

Diabetic Retinal Neurodegeneration in Experimental Research

An animal model supplies those neural and glial changes on a compressed timescale in an eye that can be measured repeatedly, so layer thickness by cross-sectional imaging and inner retinal function by electrophysiology can be followed in the same animal. It also supplies a dated onset of hyperglycemia, whether induced or genetic, so the interval between metabolic insult and neural change is known in a way a patient's history rarely allows.

What it does not supply is the human course:

• Diabetic rodents are usually followed for months, sometimes longer, rather than over the many years through which human diabetic eye disease evolves
• They are not reported to progress to proliferative retinopathy
• The visual endpoints that establish a neural deficit in people, among them contrast sensitivity, color discrimination and perimetry, require a subject who reports what they see
• Mouse and rat retinas have no macula, so inner retinal thinning in these models is measured outside the anatomy in which clinical studies of it are often sited

Rat Models of Diabetic Retinal Neurodegeneration

The rat offers a larger eye than the mouse while remaining a small-animal model, which eases injection and imaging without moving to a large species.

Published MICRON Research: Diabetic Retinal Neurodegeneration in Rats

This page lists 6 papers from the MICRON literature, published 2021 to 2025, that study diabetic retinal neurodegeneration in rats.

Of these publications:

• 6 studies used rats as the primary diabetic retinal neurodegeneration disease model.

Scope of the literature collection: Publication counts reflect studies identified and indexed in the MICRON research corpus. This collection is not intended to represent an exhaustive review of all published diabetic retinal neurodegeneration research.

Which imaging and experimental techniques are used in these studies?

Technique counts are paper-level co-occurrences and do not necessarily indicate that a technique was applied to the focal species or focal disease model.

Capabilities and Limitations of Imaging Techniques

A summary of what each imaging technique listed above can measure, the information it provides, and its limitations in research applications.

Optical Coherence Tomography

Optical coherence tomography provides high-resolution, cross-sectional images of ocular tissues in the living eye, allowing researchers to visualize structures at different depths. OCT is particularly useful for measuring tissue thickness, identifying structural abnormalities, and assessing the location and extent of tissue changes.

As a non-invasive imaging technique, OCT enables repeated measurements in the same eye over time, supporting longitudinal studies of disease progression and treatment response. Although OCT provides detailed structural information, it does not directly measure cellular activity or visual function. Tissue that appears structurally normal may still have functional abnormalities, making OCT a valuable companion to functional assessments such as electroretinography (ERG).

Electroretinography

Records the retina's electrical response to light, giving component-sensitive information about outer- and inner-retinal function. It measures function directly, which no structural method does. Full-field ERG sums across the whole retina, so a small lesion can leave the trace unchanged; focal and multifocal variants trade signal amplitude for spatial resolution.

Laser Photocoagulation Models

A laser lesion provokes a reproducible, quantifiable injury at a known time and place. Wavelength, power, duration, spot size, pulse mode, focus and lesion location together determine the injury produced, allowing laser exposure to be configured for different experimental endpoints. It is an induced injury, not the disease: it produces a lesion directly, bypassing the process that gives rise to comparable damage in patients.

Fundus Fluorescein Angiography

Fundus fluorescein angiography uses an injected fluorescent dye to visualize blood flow through the retinal and choroidal circulation. Sequential images show how vessels fill, identify areas of reduced or absent perfusion, and reveal dye leakage associated with vascular abnormalities.

This technique is particularly useful for evaluating vascular perfusion, blood-retinal barrier integrity, and abnormal vessel growth. Fluorescein angiography primarily shows dye distribution rather than the surrounding retinal tissue. It provides a two-dimensional (en face) view in which vessels at different depths may overlap. Cross-sectional and cellular structural details require other imaging methods, such as optical coherence tomography (OCT) or optical coherence tomography angiography (OCT-A). Vascular abnormalities that do not affect dye filling or produce leakage may also remain undetected.

Intravitreal Injection / Delivery

Injection into the vitreous places a substance directly into the vitreous at a known administered dose and chosen time, reducing but not eliminating systemic exposure. The injectate may be a therapeutic compound, cell preparation or viral vector, or an agent used to create the model, such as a toxin, vasoactive or excitotoxic compound, or infectious inoculum. The route bypasses surface-delivery barriers and provides direct access to the vitreous and posterior segment, but the concentration reached in a particular ocular tissue depends on distribution and clearance and is not fixed by the injected dose alone. It is invasive and discrete: each repeat dose or challenge requires another injection, and vehicle- or sham-injected controls can help separate effects of the injectate from effects of the procedure.

Topical Ophthalmic Drug Delivery

A compound applied as drops to the ocular surface. It is non-invasive and repeatable, so it supports frequent dosing without a procedure for each dose. What the route has to establish depends on the target: for an ocular-surface target, residence time and penetration into the surface tissue are the main barriers; for an intraocular anterior-segment target, the compound must cross ocular-surface and corneal or conjunctival barriers and reach an intraocular concentration sufficient for the experiment; for a posterior-segment target, additional ocular barriers separate the surface from the target and posterior-segment exposure is harder to establish.

Which MICRON systems and add-ons appear?

Which strains and genetic lines are used?

Which other species appear alongside?

What other conditions are recorded on the same papers?

Which MICRON configurations appear in this work?

Configurations recorded in these papers, and the techniques recorded alongside them.

The papers

Browse all hubs at MICRON Research Hubs. The full corpus is searchable in the reSEARCH portal.