Abstract
This study aims to explore the expression of GRP78, a marker of endoplasmic reticulum (ER) stress, in the cortex of rat brains acutely exposed to methylmercury (MeHg). Thirty Sprague-Dawley (SD) rats were randomly divided into six groups, and decapitated 6 hours (h) after intraperitoneal (i.p.) injection of MeHg (2, 4, 6, 8 or 10 mg/kg body weight) or normal saline. Protein and mRNA expression of Grp78 were detected by western blotting and real-time PCR, respectively. The results showed that a gradual increase in GRP78 protein expression was observed in the cortex of rats acutely exposed to MeHg (2, 4 or 6 mg/kg). Protein levels peaked in the 6 mg/kg group (p < 0.05 vs. controls), decreased in the 8 mg/kg group, and bottomed below the control level in the 10 mg/kg group. Parallel changes were noted for Grp78 mRNA expression. It may be implied that acute exposure to MeHg induced hormetic dose-dependent changes in Grp78 mRNA and protein expression, suggesting that activation of ER stress is involved in MeHg-induced neurotoxicity. Low level MeHg exposure may induce GRP78 protein expression to stimulate endogenous cytoprotective mechanisms.
Original language | English (US) |
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Pages (from-to) | 109-120 |
Number of pages | 12 |
Journal | Dose-Response |
Volume | 11 |
Issue number | 1 |
DOIs | |
State | Published - 2013 |
Externally published | Yes |
Keywords
- Cortex
- Endoplasmic reticulum stress
- GRP78
- Methylmercury
- Rat
ASJC Scopus subject areas
- Toxicology
- Public Health, Environmental and Occupational Health
- Health, Toxicology and Mutagenesis
- Chemical Health and Safety