Potentiation of NMDA receptor-mediated synaptic transmission at the parabrachial-central amygdala synapses by CGRP in mice
نویسندگان
چکیده
The capsular part of the central amygdala (CeC) is called the "nociceptive amygdala," as it receives nociceptive information from various pathways, including monosynaptic input from the lateral part of the parabrachial nucleus (LPB), a major target of ascending neurons in the spinal and medullary dorsal horn. LPB-CeC synaptic transmission is mediated by glutamate but the fibers from the LPB also contain calcitonin gene-related peptide (CGRP) and the CeC is rich in CGRP-binding sites. CGRP might be released in response to strong nociception and activate these CGRP receptors. Though it has been shown that CGRP affects the excitatory postsynaptic current (EPSC) amplitude at this synapse in a manner sensitive to NMDA receptor (NMDA-R) blockers, the effect of CGRP on postsynaptic NMDA-R-mediated current recorded in isolation has never been directly examined. Thus, we evaluated the effects of CGRP on NMDA-R-mediated EPSCs that were pharmacologically isolated in brain slices from naïve mice. CGRP significantly increased the amplitude of EPSCs mediated by NMDA-Rs in a manner dependent on protein kinase A activation, but not that mediated by alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptors, in concentration-dependent and antagonist-sensitive manners. This CGRP-induced potentiation of synaptic NMDA-R function would have a potent impact on the strengthening of the nociception-emotion link in persistent pain.
منابع مشابه
P19: Long-Term Potentiation
The term synaptic plasticity points to a series of persistent changes related to the activity of synapses. Long-term potentiation (LTP) is a reflection of synaptic plasticity that has an important role in learning and memory. LTP is a long-lasting increase of synaptic activity due to enhancement of excitatory synaptic transmission after a high-frequency train of electrical stimulations. Differe...
متن کاملThe effect of ketamine on NMDA receptor-mediated LTP depends on ketamine effects on non-NMDA-mediated synaptic transmission in CA1 area of rat hippocampal slices
It has been reported that ketamine as an uncompetitive N-methyl-D-aspartate (NMDA) receptor antagonist has also non-NMDA receptor antagonist properties. We recently found that ketamine (20 ?M) affected differently induction of NMDA receptor-mediated long-term potentiation (LTP) when administered 30 min prior to tetanic Primed-Bursts (PBs) stimulation. On the other hand, ketamine also influenced...
متن کاملThe effect of ketamine on NMDA receptor-mediated LTP depends on ketamine effects on non-NMDA-mediated synaptic transmission in CA1 area of rat hippocampal slices
It has been reported that ketamine as an uncompetitive N-methyl-D-aspartate (NMDA) receptor antagonist has also non-NMDA receptor antagonist properties. We recently found that ketamine (20 ?M) affected differently induction of NMDA receptor-mediated long-term potentiation (LTP) when administered 30 min prior to tetanic Primed-Bursts (PBs) stimulation. On the other hand, ketamine also influenced...
متن کاملP6: Metabotropic Glutamate Receptor-Dependent Role in the Formation of Long-Term Potentiation
Long-term potentiation (LTP) is a reflection of synaptic plasticity that induced by specific patterns of synaptic activity and has an important role in learning and memory. The first clue of the potential role of glutamate receptors in LTP was in 1991 with the observation that the mGluR agonists 1-amino-1, 3-cyclopentanedicarboxylic acid (ACPD), increased LTP. Studies have shown that ACPD induc...
متن کاملFacilitation of synaptic transmission and pain responses by CGRP in the amygdala of normal rats
Calcitonin gene-related peptide (CGRP) plays an important role in peripheral and central sensitization. CGRP also is a key molecule in the spino-parabrachial-amygdaloid pain pathway. Blockade of CGRP1 receptors in the spinal cord or in the amygdala has antinociceptive effects in different pain models. Here we studied the electrophysiological mechanisms of behavioral effects of CGRP in the amygd...
متن کامل