Amygdala N-methyl-D-aspartate receptors participate in the induction of long-term potentiation in the dentate gyrus in vivo.

We investigated the effects of injection of N-methyl-D-aspartate (NMDA) receptor antagonists, 2-amino-5-phosphonovalerate (APV) and 7-chlorokynurenate (7-Cl-Kyn), into the basolateral amygdala (BLA) on long-term potentiation (LTP) in the medial perforant path-dentate gyrus granule cell synapses of anesthetized rats. Injection of APV or 7-Cl-Kyn into the ipsilateral BLA did not affect the baseline synaptic responses, but significantly attenuated the dentate gyrus LTP induced by tetanic stimulation. Injection of APV into the contralateral BLA did not affect the induction of LTP. When APV was injected after tetanic stimulation, it did not affect the maintenance phase of LTP. These results suggest that NMDA receptors in the ipsilateral BLA partly participate in the induction of LTP in the dentate gyrus in vivo.