Abstract
Aim:
To investigate the changes in the spontaneous neuronal excitability induced by astragaloside IV (AGS-IV) in the cultured hippocampal network.
Methods:
Hippocampal neurons in culture for 9-11 d were used for this study. The spontaneous synaptic activities of these hippocampal neurons were examined by Ca2+ imaging and whole-cell patch-clamp techniques. In total, 40 mg/L AGS-IV dissolved in DMSO and 2 mL/L DMSO were applied to the neurons under a microscope while the experiments were taking place.
Results:
AGS-IV inhibited the frequencies of synchronized spontaneous Ca2+ oscillations to 59.39%±3.25% (mean±SEM), the spontaneous postsynaptic currents to 43.78%±7.72% (mean±SEM), and the spontaneous excitatory postsynaptic currents to 49.25%±7.06% (mean±SEM) of those of the control periods, respectively, at 16 min after the AGS-IV applications. AGS-IV also decreased the peak values of the voltage-gated K+ and Na+ channel currents at that time point.
Conclusion:
These results indicate that AGS-IV suppresses the spontaneous neuronal excitabilities effectively. Such a modulation of neuronal activity could represent new evidence for AGS-IV as a neuroprotector.
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This work was supported by a grant from the Major State Basic Research Development Program of China (973 Program) (No 2005CB522503) and the Natural Science Foundation of Beijing (Grant No 5052015).
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Zhu, Sq., Qi, L., Rui, Yf. et al. Astragaloside IV inhibits spontaneous synaptic transmission and synchronized Ca2+ oscillations on hippocampal neurons. Acta Pharmacol Sin 29, 57–64 (2008). https://doi.org/10.1111/j.1745-7254.2008.00712.x
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DOI: https://doi.org/10.1111/j.1745-7254.2008.00712.x
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