RESUMEN
Objective To compare the effects of different intervals of theta burst stimulation(TBS) on the expression of long-term potentiation(LTP) and to explore whether LTP is tyrosine protein kinase(TPK)-dependent.in basolateral amygdala(BLA).Methods Basolateral amygdala slices of rats were prepared.Field excitatory post-synaptic potentials(field potential,fEPSPs) of BLA were recorded by stimulating the external capsule.Two TBS's were applied to induce LTP in BLA.Each TBS included a brief,high-frequency pulse train(5 pulses at 100 Hz) given at the theta-rhythm(5Hz) for 4 seconds.Experiments compare the effects of different intervals of two TBS's on the expression of LTP in BLA.The role of tyrosine protein kinase(TPK) on LTP was then determined using bath application of TPK inhibitor genistein.Results Two TBS's of 10 seconds interval failed to induce LTP in BLA.However,two TBS's increased to 10 min and 30 min intervals,individually,both types of stimulations enhanced f-EPSPs.The enhanced f-EPSPs lasted for more than 30 min.LTP induced by two TBS's of 10 min and 30 min interval were blocked by the TPK inhibitor genistein.Conclusion Two TBS's of 10 min intervals was better at the induction of LTP in BLA.The activation of TPK was possibly involved in the induction and maintenance of LTP in the amygdala.