High intraocular pressure produces learning and memory impairments in rats

Brain Res. 2017 Nov 15:1675:78-86. doi: 10.1016/j.brainres.2017.09.001. Epub 2017 Sep 8.

Abstract

Primary open angle glaucoma (POAG) is a leading cause of irreversible blindness worldwide. Previous MRI studies have revealed that POAG can be associated with alterations in hippocampal function. Thus, the aim of this study was to investigate a relationship between chronic high intraocular pressure (IOP) and hippocampal changes in a rat model. We used behavioural tests to assess learning and memory ability, and additionally investigated the hippocampal expression of pathological amyloid beta (Aβ), phospho-tau, and related pathway proteins. Chronic high IOP impaired learning and memory in rats and concurrently increased Aβ and phospho-tau expression in the hippocampus by altering the activation of different kinase (GSK-3β, BACE1) and phosphatase (PP2A) proteins in the hippocampus. This study provides novel evidence for the relationship between high IOP and hippocampal alterations, especially in the context of learning and memory.

Keywords: Amyloid beta; Hippocampus; Intraocular pressure; Learning and memory; Tau.

MeSH terms

  • Animals
  • Hippocampus / metabolism
  • Hippocampus / pathology
  • Intraocular Pressure / physiology*
  • Male
  • Maze Learning / physiology*
  • Memory Disorders / etiology
  • Memory Disorders / metabolism
  • Memory Disorders / pathology*
  • Ocular Hypertension / complications
  • Ocular Hypertension / metabolism
  • Ocular Hypertension / pathology*
  • Rats
  • Rats, Sprague-Dawley