title: Presynaptic Ca²⁺-permeable AMPA-receptors modulate paired-pulse depression in nociceptive sensory synapses.
abstract: The role of Ca(2+)-permeable AMPA-receptors (CP-AMPARs) in the induction of paired-pulse depression (PPD) at glutamatergic nociceptive sensory synapses was examined in co-culture of rat's dorsal root ganglion and dorsal horn neurons. CP-AMPARs make a considerable contribution to excitatory postsynaptic currents recorded in DH neurons following action potential generation in nociceptive DRG neurons. Activation of CP-AMPARs during fast synaptic transmission induces strong PPD (with a 200 ms inter-pulse interval). Blockage of CP-AMPARs with Naspm (100 μM) results in most cases in a significant reduction of the PPD magnitude, also reversing to paired-pulse facilitation in some cases. However, loading of postsynaptic DH neurons with BAPTA (10 mM) did not alter the effect of Naspm (100 μM) on the paired-pulse ratio. Our data provide evidence that presynaptic CP-AMPARs in nociceptive sensory synapses regulate the magnitude of PPD and that postsynaptic Ca(2+)-permeable glutamatergic receptors are not required for PPD induction.
authors.affiliation: Bogomoletz Institute of Physiology, National Academy of Sciences of Ukraine, 4, Bogomoletz str., Kiev 01024, Ukraine. Electronic address: shypshyna.mariia@gmail.com.
authors.forename: Mariia S
authors.initials: MS
authors.lastname: Shypshyna
authors.affiliation: Bogomoletz Institute of Physiology, National Academy of Sciences of Ukraine, 4, Bogomoletz str., Kiev 01024, Ukraine. Electronic address: nsvesel@biph.kiev.ua.
authors.forename: Nikolai S
authors.initials: NS
authors.lastname: Veselovsky
mesh_terms: D000200:Action Potentials; D000818:Animals; D000831:Animals, Newborn; D002118:Calcium / Q000378:metabolism*; D002478:Cells, Cultured; D018920:Coculture Techniques; D019706:Excitatory Postsynaptic Potentials; D005727:Ganglia, Spinal / Q000166:cytology; D018698:Glutamic Acid / Q000378:metabolism; D009473:Neuronal Plasticity; D009619:Nociceptors / Q000166:cytology / Q000502:physiology*; D020671:Posterior Horn Cells / Q000166:cytology / Q000502:physiology*; D017208:Rats, Wistar; D018091:Receptors, AMPA / Q000378:metabolism*; D017661:Receptors, Presynaptic / Q000378:metabolism*; D013569:Synapses / Q000502:physiology*; D009435:Synaptic Transmission
chemical_list: D018091:Receptors, AMPA; D017661:Receptors, Presynaptic; D018698:Glutamic Acid; D002118:Calcium
keywords: Ca(2+)-permeable AMPA-receptors; Co-culture; Nociceptive sensory synapses; Paired-pulse depression