Retinal microglia - A key player in healthy and diseased retina.

Microglia, the resident immune cells of the brain and retina, are constantly engaged in the surveillance of their surrounding neural tissue. During embryonic development they infiltrate the retinal tissues and participate in the phagocytosis of redundant neurons. The contribution of microglia in maintaining the purposeful and functional histo-architecture of the adult retina is indispensable.

Dynamic Responses in Retinal Vessel Caliber With Flicker Light Stimulation and Risk of Diabetic Retinopathy and Its Progression.

Purpose: This study investigated the associations between the responses of retinal vessels to flickering light and the incidence and progression of diabetic retinopathy (DR).

Methods: A prospective cohort study of adult subjects with diabetes mellitus. The dynamic vessel analyser (DVA) was used to measure retinal vascular dilatation in response to diffuse illuminance flicker.

Glutamate Inhibits the Pro-Survival Effects of Insulin-Like Growth Factor-1 on Retinal Ganglion Cells in Hypoxic Neonatal Rat Retina.

Glutamate that accumulates in injured brain tissue has been shown to hinder the neuroprotection rendered by insulin-like growth factor-1 (IGF-1). However, its role in attenuating the neuroprotective effect of IGF-1 in the hypoxic retina is unknown and the current study was aimed at elucidating this. One-day-old Wistar rats were exposed to hypoxia for 2 h and the retinas were studied at 3 h to 14 days after exposure.

Relationship of systemic endothelial function and peripheral arterial stiffness with diabetic retinopathy.

Background: To investigate possible associations between diabetic retinopathy (DR) and systemic vascular endothelial function and arterial stiffness measured using reactive hyperaemia peripheral arterial tonometry.

Methods: This was a cross-sectional observational clinical study. Subjects with diabetes were recruited and DR was graded from retinal photographs.

Vascular changes in the developing rat retina in response to hypoxia.

This study was carried out to investigate the roles of tight junction (TJ) proteins and other factors in the increased permeability of the blood retinal barrier (BRB) affecting the immature neonatal retina following a hypoxic insult. The expression of endothelial TJ proteins such as claudin-5, occludin and zonula occludens-1 (ZO-1) and endothelial cell specific molecule-1 (ESM-1), and associated structural changes in the blood vessels were analyzed in the retinas of 1-day-old Wistar rats subjected to hypoxia for 2 h and subsequently sacrificed at different time points ranging from 3 h to 14 d. The mRNA and protein expression of claudin-5, occludin & ZO-1 was found to be reduced in the hypoxic retina, although, at the ultrastructural level, the TJ between the endothelial cells and retinal pigment epithelial cells appeared to be intact.