The Effect of Acutely Elevated Intraocular Pressure on the Functional and Blood Flow Responses of the Rat Retina to Flicker Stimulation

Investigative Ophthalmology & Visual Science
Bingyao TanKostadinka Bizheva

Abstract

To evaluate the effect of acutely elevated intraocular pressure (IOP) on the functional and blood flow responses of the rat retina to flicker stimulation. Brown Norway (n = 15) rats were dark-adapted before ketamine/xylazine anesthesia. IOP was raised acutely in one eye to ∼45 mm Hg with a vascular loop. In 11 rats, white light flicker stimulus (10 Hz, 2 seconds duration, 0.80 log scotopic cd·s/m2) was applied before and during IOP elevation, and 10 minutes after loop removal. Changes in the total retinal blood flow (TRBF) and retinal function induced by the visual stimulus were measured simultaneously with a combined optical coherence tomography (OCT) + electroretinography (ERG) system. Systemic blood pressure was measured in the remaining four rats frequently from 10 to 90 minutes post anesthesia injection. The systemic blood pressure remained at 99 ± 4 mm Hg throughout the measurements (n = 4). Under normal IOP, the TRBF was 5.6 ± 1.9 μL/min, and the average retinal blood vessel size (BVS) in the vicinity of the optic nerve head (ONH) was 44.1 ± 4.5 μm. During IOP elevation, the TRBF was significantly lower (3.8 ± 1.2 μL/min, P < 0.01) and the BVS was significantly smaller (35.1 ± 2.6 μm, P < 0.01). Both TRBF and BVS returne...Continue Reading

Related Concepts

Trending Feeds

COVID-19

Coronaviruses encompass a large family of viruses that cause the common cold as well as more serious diseases, such as the ongoing outbreak of coronavirus disease 2019 (COVID-19; formally known as 2019-nCoV). Coronaviruses can spread from animals to humans; symptoms include fever, cough, shortness of breath, and breathing difficulties; in more severe cases, infection can lead to death. This feed covers recent research on COVID-19.

Blastomycosis

Blastomycosis fungal infections spread through inhaling Blastomyces dermatitidis spores. Discover the latest research on blastomycosis fungal infections here.

Nuclear Pore Complex in ALS/FTD

Alterations in nucleocytoplasmic transport, controlled by the nuclear pore complex, may be involved in the pathomechanism underlying multiple neurodegenerative diseases including Amyotrophic Lateral Sclerosis and Frontotemporal Dementia. Here is the latest research on the nuclear pore complex in ALS and FTD.

Applications of Molecular Barcoding

The concept of molecular barcoding is that each original DNA or RNA molecule is attached to a unique sequence barcode. Sequence reads having different barcodes represent different original molecules, while sequence reads having the same barcode are results of PCR duplication from one original molecule. Discover the latest research on molecular barcoding here.

Chronic Fatigue Syndrome

Chronic fatigue syndrome is a disease characterized by unexplained disabling fatigue; the pathology of which is incompletely understood. Discover the latest research on chronic fatigue syndrome here.

Evolution of Pluripotency

Pluripotency refers to the ability of a cell to develop into three primary germ cell layers of the embryo. This feed focuses on the mechanisms that underlie the evolution of pluripotency. Here is the latest research.

Position Effect Variegation

Position Effect Variagation occurs when a gene is inactivated due to its positioning near heterochromatic regions within a chromosome. Discover the latest research on Position Effect Variagation here.

STING Receptor Agonists

Stimulator of IFN genes (STING) are a group of transmembrane proteins that are involved in the induction of type I interferon that is important in the innate immune response. The stimulation of STING has been an active area of research in the treatment of cancer and infectious diseases. Here is the latest research on STING receptor agonists.

Microbicide

Microbicides are products that can be applied to vaginal or rectal mucosal surfaces with the goal of preventing, or at least significantly reducing, the transmission of sexually transmitted infections. Here is the latest research on microbicides.