The effect of chronic stress and its preconditioning on spatial memory as well as hippocampal LRP1 and RAGE expression in a streptozotocin-induced rat model of Alzheimer’s disease

Abstract

According to available evidence, prolonged or chronic exposure to stress is detrimental to various brain structures, including the hippocampus. The current study examined the expression of two critical bloodbrain barrier receptors required for amyloid-beta clearance to understand better the mechanism by which chronic stress impairs learning and memory in patients with Alzheimer's disease (AD). Rats were bilaterally injected with streptozotocin (STZ) (3mg/kg) using the intracerebroventricular (ICV) technique to induce the Alzheimer's model. Additionally, they were subjected to foot shock (1mA, 1Hz) for 10s every 60s (1h/day) for ten consecutive days prior to and following STZ injection. The Morris Water Maze (MWM) test was used to assess spatial learning and memory. Real-time PCR was used to determine Lowdensity lipoprotein receptor-related protein-1 (LRP1) and receptor for advanced glycation end-products (RAGE) mRNA levels in the hippocampus. Moreover, the animals' body weights were determined as physiological parameters in all groups. The results indicated that 10-day chronic electric foot shock stress reduced body weight, impaired spatial learning and memory, decreased hippocampal LRP1 mRNA expression, and increased hippocampal RAGE mRNA expression in a rat AD model. It can be concluded that chronic stress in conjunction with AD alters the expression of LRP1 and RAGE in the hippocampus. The ndings pave the way for scientists to develop novel treatment strategies for AD.

Влияние Стресса На Зубочелюстную Систему

“…Исследуются изменения тканевого метаболизма под влиянием различных стрессфакторов и их роль в генезе психосоматических заболеваний и преждевременного старения организма за счет активации перекисного окисления липидов (ПОЛ) [8]. Показана роль тиреоидных гормонов в стресс-лимитирующей системе организма, определен их антиоксидантный эффект при стрессе [2].…”

“…Не оставляет сомнений взаимосвязь физиологических и биохимических параметров организма с психологическими и поведенческими реакциями на стресс [9]. Выявлена взаимосвязь между типом вегетативного тонуса организма и скоростью слюноотделения, водородным показателем, уровнем иммуноглобулина G, кальция, характером микрокристаллизации нестимулированной ротовой жидкости [8].…”