Effects of genistein on neuronal discharges in rat hippocampal CA1 area
- VernacularTitle:三羟异黄酮对大鼠海马CA1区神经元自发放电的影响
- Author:
Wang RU
1
;
Wu YU-MING
;
Zhang HAO
;
Wang XIN
;
He RUI-RONG
Author Information
1. 河北医科大学
- Keywords:
hippocampal slice;
GST;
TEA;
L-NAME;
L-glutamate
- From:
Neuroscience Bulletin
2005;21(6):380-384
- CountryChina
- Language:Chinese
-
Abstract:
Objective To examine the effects of genistein ( GST ) on the discharges of neurons in CA1 area of hippocampal slices. Results (1) In response to the application of GST (10, 50, 100 μmol/L; n=48) into the perfusate for 2 min, the spontaneous discharge rates (SDR) of 46/48 ( 95.83 % ) neurons were significantly decreased in a dose-dependent manner. (2) In 9 neurons, the G protein-coupled inwardly rectifying K+ (GIRK) channels antagonist, tetraethylammonium ( TEA 1mmol/L ) completely blocked the inhibitory effect of GST (50 μmol/L). (3) Application of nitric oxide synthase ( NOS ) inhibitor NG-nitro-L-arginine methyl ester ( L-NAME, 50 μmol/L ) into the perfusate for 2 min significantly augmented the SDR of 9/10( 90.0% ) neurons , then GST ( 50 μmol/L ) applied into the perfusate reduced the increased SDR of all 9/9 ( 100% ) neurons. (4) Pretreatment with L-glutamate ( L-Glu, 0.2 mmol/L ) led to a marked increase in the SDR of all 11 ( 100% ) neurons in an epileptiform pattern. The increased discharges were also suppressed significantly after GST (50 μmol/L) was applied into the perfusate for 2 min. Conclusion GST can inhibit the electrical activity of CA1 neurons. The inhibitory effect may be related to the activation of GIRK which induce K+ outward current and then engender the cell membrane hyperpolarization, and to the increased production of NO increase,which indicated that GST play a protective role on the central neurons.
