title: [Involvement of excitatory amino acid system in astrocytes activation caused by dimethoate].
abstract: OBJECTIVE
  To study the involvement of excitatory amino acid system in astrocytes activation caused by dimethoate.
  
  
  METHODS
  Pure-cultured astrocytes were gained by three passages from primary cultured rat nerve cells, then treated with 10(-6),10(-5),10(-4) mol/L dimethoate for 48 h, 50 micromol/L and 100 micromol/L MK801, a NMDA receptor blocker, was used to intervene the effects induced by 10(-4) mol/L dimethoate. HPLC-FLD was utilized to measure the concentrations of excitatory amino acid (EAA), RT-PCR was used to detect the expression levels of NR2B, GLT-1, GLAST, GFAP and S100beta mRNA, and immunofluorescence staining method was applied to measure the expression levels of GFAP and S100beta proteins.
  
  
  RESULTS
  The expression levels of GLAST mRNA in all exposure groups were 67.8%, 68.6% and 76.2% of control level, respectively, which were significantly lower than that of control group (P < 0.05); The concentrations of EAA significantly decreased in 10(-4) mol/L dimethoate group, as compared with control group (P < 0.01); the expression levels of GFAP mRNA in 10(-4) mol/L dimethoate group, of S100beta mRNA in 10(-5) mol/L dimethoate group, of GFAP protein in 10(-4) mol/L and 10(-5) mol/L dimethoate groups and S100beta protein in 10(-4) mol/L dimethoate group were significantly higher than those in control group (P < 0.01). The expression levels of GLT-1 and GLAST mRNA in 10(-4) mol/L dimethoate plus 50 micromol/L or 100 micromol/L MK801 groups increased significantly, as compared with 10(-4) mol/L dimethoate group (P < 0.01), the expression levels of NR2B mRNA in 10(-4) mol/L dimethoate plus 50 micromol/L or 100 micromol/L MK801 groups increased significantly, as compared with control group (P < 0.05 or P < 0.01); the concentration of Glu in 10(-4) mol/L dimethoate plus 100 micromol/L MK801 group increased significantly, as compared with 10(-4) mol/L dimethoate group (P < 0.01); the expression levels of GFAP mRNA and protein in 10(-4) mol/L dimethoate plus 50 micromol/L or 100 micromol/L MK801 groups decreased significantly (P < 0.01); S100beta protein expression level in 50 micromol/L MK801 intervention group was significantly higher than thatl in control group (P < 0.01).
  
  
  CONCLUSIONS
  Excitatory amino acid system involved in astrocytes activation caused by dimethoate. MK801 was useful to control astrocytes gliosis.
authors.affiliation: School of Public Health/MOE Key Lab for Public Health/ WHO Collaborating Center for Occupational Health, Fudan University, Shanghai 200032, China.
authors.forename: Hong-Mei
authors.initials: HM
authors.lastname: Cui
authors.forename: Xiu-Li
authors.initials: XL
authors.lastname: Chang
authors.forename: Fu
authors.initials: F
authors.lastname: Xu
authors.forename: Qing
authors.initials: Q
authors.lastname: Wu
authors.forename: Zhi-Jun
authors.initials: ZJ
authors.lastname: Zhou
mesh_terms: D000818:Animals; D001253:Astrocytes / Q000187:drug effects* / Q000378:metabolism*; D002478:Cells, Cultured; D004117:Dimethoate / Q000633:toxicity*; D016291:Dizocilpine Maleate / Q000494:pharmacology; D018846:Excitatory Amino Acids / Q000378:metabolism*; D051381:Rats; D016194:Receptors, N-Methyl-D-Aspartate / Q000037:antagonists & inhibitors
chemical_list: D018846:Excitatory Amino Acids; D016194:Receptors, N-Methyl-D-Aspartate; D016291:Dizocilpine Maleate; D004117:Dimethoate