title: [Effects of ginkgo biloba extracts on NMDA-activated currents in acutely isolated rat hippocampal neurons].
abstract: OBJECTIVE
  To investigate effect of ginkgo biloba extract (GBE) on N-methyl-D-aspartate (NMDA)-activated currents (I(NMDA)) and evaluate further the modulatory effects of Micro-GBE/Nano-GBE.
  
  
  METHODS
  By means of whole-cell patch clamp technique, NMDA-activated currents from acutely isolated rat hippocampal neurons were recored.
  
  
  RESULTS
  The majority of the neurons examined (81.8%, 90/110) were sensitive to NMDA (1 mmol/L) and its co-agonist Gly (10 micromol/L). NMDA activated an inward current, which manifested apparent desensitization and could be blocked by its specific antagonist MK-801. After the neurons were treated with Micro/Nano GBE (0.1 mg/ml) followed by the application of NMDA (1 mmol/L) and Gly (10 micromol/L) for 30 s, it was show that NMDA-activated currents were obviously inhibited (P < 0.01, n = 8). The inhibitory rate were 40% +/- 17% and 64% +/- 15% respectively. It showed that the modulatory effect of Nano-GBE (dissolved in the stander extracellular solution) on NMDA-activated current was significantly higher than that of Micro-GBE (dissolved in DMSO) (P < 0.05).
  
  
  CONCLUSIONS
  The inward currents activated by NMDA could be depressed by Micro-GBE and Nano-GBE. The modulatory effects of GBE on NMDA-activated current are expected to contribute to the neuroprotective effects of ginkgo biloba extracts. In addition, at the same concentration, the modulatory effect of Nano-GBE on NMDA-activated current is better than that of Micro-GBE.
authors.affiliation: Department of Physiology and Institute for Brain Disorder and Disease, Dalian Medical University, Dalian 116027, China.
authors.forename: Shao
authors.initials: S
authors.lastname: Li
authors.forename: Chang-Kai
authors.initials: CK
authors.lastname: Sun
authors.forename: Xin-Cai
authors.initials: XC
authors.lastname: Ji
authors.forename: Jian
authors.initials: J
authors.lastname: Zhang
mesh_terms: D000818:Animals; D002478:Cells, Cultured; D020441:Ginkgo biloba; D006624:Hippocampus / Q000187:drug effects / Q000502:physiology*; D016202:N-Methylaspartate / Q000494:pharmacology; D009474:Neurons / Q000187:drug effects / Q000502:physiology*; D018408:Patch-Clamp Techniques; D010936:Plant Extracts / Q000494:pharmacology*; D051381:Rats; D017207:Rats, Sprague-Dawley; D016194:Receptors, N-Methyl-D-Aspartate / Q000187:drug effects
chemical_list: D010936:Plant Extracts; D016194:Receptors, N-Methyl-D-Aspartate; D016202:N-Methylaspartate