Effect of adenosine on epileptiform discharge of hippocampal neurons from lithium chloride-pilocarpine induced epileptic rats / 中华神经科杂志

ABSTRACT

Objective To use the whole-cell patch clamp recording to observe the effect of adenosine on hippocampus pyramidal neurons epileptiform discharge from lithium chloride-pilocarpine induced epileptic rats.Methods Twenty adult male and female SD rats (weighing about 200 g) were selected and were narcotized by 10％ chloral hydrate intraperitoneal injection.The whole brain was removed, then chopped into 350 μm thick slices.The brain slices were transferred to 37 ℃ preheated artificial cerebrospinal fluid for 1 h and then transferred to 23 ℃ for 30 min.Action potentials (AP) and evoked excitatory postsynaptic currents (eEPSCs) of brain slices neurons were recorded by whole-cell patch clamp, in addition, 25 μmol/L adenosine was used to observe its effect on AP and eEPSCs.Results With the application of current clamp technique, the application of adenosine (25 μmol/L) significandy decreased the numbers of AP in epileptic neurons (P ＜ 0.01) compared with the normal neurons ((0.50 ± 0.06) nA), and eEPSCs amplitude of epileptic neurons increased significantly ((1.44 ± 0.06) nA;independent sample t test, t =30.99, P ＜ 0.01) by voltage clamp.Bath application of adenosine (25 μmol/L) significantly reduced eEPSCs amplitude ((0.66 × 0.06) nA), while application of A1 receptor inhibitor DPCPX partially reversed this effect ((0.92 × 0.06) nA;one-way analysis of variance and q test, F =266.3, q =9.81, P ＜ 0.01).Conclusion Adenosine possesses a strong inhibitory effect on epileptic hippocampal brain slices discharge, which is mediated by its effect on eEPSCs.