[Abstract Title]. - Society for Neuroscience

memory. ATP is released from both neurones and astrocytes and activates ionotropic (P2X) or
metabotropic (P2Y) purine receptors found on neurones, astrocytes or capillaries in the central
nervous system. ATP is hydryolsed to ADP and adenosine causing presynaptic inhibition. All
three nucleotides activate different purinergic receptors with distinct pharmacology. We have
discovered which receptors are involved in memory consolidation formation at 0-2.5 min and at
30-35 min after training.
In a discriminative avoidance task in young chicks where a single, brief (10 sec) learning
experience with a bitter tasting bead is used to dissect out the roles for activation of the different
purinergic receptors. The discrete timing of this task allows accurate „real-time‟ measurements
for injection and testing of memory processes. A weak version of this task where memory lasts
for only 30 min, presents the opportunity to enhance memory consolidation and facilitate the
formation of long-term memory.
In the chick hippocampus, glutamate release occurs for up to 2.5 min after training and then
again around 30 min post-training, a time during which the previously labile memory
consolidates into permanent memory. We have shown that activation or inhibition of NMDA
receptors in the chick hippocampus can enhance or inhibit storage at these two times. AMPA
receptors antagonists also inhibit memory at these same times.
We have found that central, hippocampal injections of ATP (1nmol/hemisphere) promotes the
formation of memory for weakly-reinforced learning. To understand which of the purinergic
receptor subtypes are involved in memory processing and how, we have injected selective
purinergic agonists and antagonists where available and examined their effects on memory.
ATP-γ-S, ADP-β-S, and UTP all enhanced weak learning when administered at similar time
periods.
Disclosures: D.N. Bowser, None; M.E. Gibbs, None.
Poster
242. Glial Neuronal Interactions: Glutamate and Calcium
Time: Sunday, November 16, 2008, 1:00 pm - 5:00 pm
Program#/Poster#: 242.3/H10
Topic: B.11.a. Synapses
Support: MEC (BFU2007-64764)
European Union (Health-F2-2007-202167)
Title: Astrocyte-induced long-term potentiation of transmitter release requires nitric oxide
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