آميگدال تاثير بر شدت تشنج هاي ناشي از كيندلينگ قشر پيريفورم ندارد A1 فعاليت گيرنده هاي آدنوزيتي

Adenosme A1 receptors of amygdala has not anticonvulsant effects on piriform cortex kindled seizures in rats

Introduction: Adenosine is an endogenous anticonvulsant which exerts its anticonvulsant effects through adenosine A I receptors. As the piriform/amygdala is a critical circuit for limbic seizure propagation, in this study the role ofamygdala A I receptors on piriform cortex kindled seizures was investigated. Materials and Methods: Rats were kindled by daily electrical stimulation of piriform cortex. In the first experiment fully kindled animals received intra-amygdala N6-cyclohexyladenosine (CHA; 10-500 u,M, a selective A I receptor) or 2% lidocaine (for reversal neuronal inhibition) bilaterally. 5 min later, animals were stimulated and seizure parameters were measured. In the second experiment, the effect of daily microinjection of CHA (100 ^M) into the amygdala on piriform cortex kindling rate was investigated. Results: Different doses of CHA had no effect on kindled seizure parameters. On the other hand, intra-amygdala 2% lidocaine reduced the kindled seizures severity. There were significant increase in stage 4 latency and decrease in stage 5 duration. Also, daily intra-amygdala CHA had no significant effect on kindling rate. Conclusion: The amygdala neuronal activity has a role in propagation of epileptic seizures from piriform cortex. Elimination of this activity by lidocaine decreases the severity of piriform cortex kindled seizures. However, the amygdala A I receptors have no role in this regard.