The effect of coriaria lactone on NMDA receptor mediated currents in rat hippocampal CA1 neurons

Abstract

To investigate the exact mechanism of epileptogenesis induced by coriaria lactone (CL), the effect of CL on NMDA receptor mediated current (I_Asp) in rat hippocampal CA1 neurons was investigated by using nystatin perforated whole-cell patch clamp. 10⁻⁶–10⁻⁴ mol/L Asp acted on NMDA receptors and elicited an inward current (I_Asp) at a holding potential (V_H) of -40 mV in presence of 10⁻⁶ mol/L glycine and absence of Mg²⁺ extracellularly. CL enhanced NMDA receptor mediated current induced by Asp, but had no effect on threshold concentration, EC₅₀, Hill coefficient as well as maximal-effect concentration and reversal potential of I_Asp. The effect had no relationship with holding potential. These results showed that CL could enhance NMDA receptor mediated current to increase [Ca²⁺]_i of neurons by acting on Gly site, thereby inducing epilepsy.

Keywords

coriaria lactone / NMDA receptor / nystatin perforated whole-cell patch clamp / hippocampal CA1 neurons

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