Presynaptic N-methyl-d-aspartate receptors at the parallel fiber–Purkinje cell synapse

AUTOR(ES)

Casado, M.

FONTE

The National Academy of Sciences

RESUMO

At the cerebellar synapse between the parallel fibers (PFs) and the Purkinje cells in the cerebellum, we have found that application of N-methyl-d-aspartate (NMDA) reversibly depresses the postsynaptic current. We present evidence that this depression involves NMDA receptors located on the presynaptic axons and requires that the NMDA application be combined with action potentials in the PFs. Unexpectedly, unlike other modulations mediated by presynaptic receptors, the NMDA-induced inhibition does not involve a depression of transmitter release. Because it is blocked by both nitric oxide synthase and soluble guanylate cyclase inhibitors, we propose that it involves a trans-synaptic mechanism in which NO released by the PFs decreases the glutamate sensitivity of the Purkinje cell.

Documentos Relacionados

• Signal transmission in the parallel fiber-Purkinje cell system visualized by high-resolution imaging.
• Alternative splicing generates functionally distinct N-methyl-D-aspartate receptors.
• Synaptic transmission at N-methyl-D-aspartate receptors in the proximal retina of the mudpuppy.
• Isolation of glutamate transport-coupled charge flux and estimation of glutamate uptake at the climbing fiber–Purkinje cell synapse
• Evidence for presynaptic N-methyl-D-aspartate autoreceptors in the spinal cord dorsal horn.