AMPA receptor subunit expression in the cuneate nucleus of adult squirrel monkeys after peripheral nerve injury

Abstract

The primate somatosensory system provides an excellent model system with which to investigate adult neural plasticity. Here, we report immunohistochemical staining data for the GluR1 and GluR2/3 AMPA receptor subunits in the cuneate nucleus of adult squirrel monkeys one week after median nerve compression. These data are compared to subunit changes in the area 3b cortex of the same animals. We report differences between control and deprived brainstem implying that deprivation induced changes in subunit expression mirror those reported in the cortex. There are significant increases in GluR1 receptor subunit staining intensity and significant decreases in GluR2/3 receptor subunit staining intensity. This pattern of expression resembles receptor configurations reported in developing sensory systems. Taken together, these results suggest that the brainstem and the cortex initially progress through a phase of developmental recapitulation prior to the onset of NMDA mediated adult somatosensory reorganization.

AMPA and GABAA/B receptor subunit expression in the cuneate nucleus of adult squirrel monkeys during peripheral nerve regeneration

“…Specifically, we have investigated receptor subunit specific changes that occur within the cortex and brainstem during recovery from peripheral nerve compression. [45, 46, 47, 51]. The current study extends these investigations of AMPA and GABA receptor subunits to the cuneate nucleus one and five months after nerve compression.…”

“…Previously we have reported that brainstem and cortex undergo a period of developmental recapitulation around 1 week after nerve injury [45, 46, 51]. Developmental plasticity happens considerably faster (hours/days) than more prolonged forms of adult plasticity (weeks/months).…”

“…Methods for nerve injury, immunohistochemical staining, and data quantification have been previously described in detail [45,46,47,51]. All procedures were approved by the Indiana University Institutional Animal Care and Use Committee.…”

Food restriction induces synaptic incorporation of calcium‐permeable AMPA receptors in nucleus accumbens

“…In addition to LTP, in which CP-AMPARs are incorporated into the synaptic membrane during the initial stage of targeted synaptic strengthening (Plant et al, 2006;Yang et al, 2010), more widespread synaptic incorporation of CP-AMPARs occurs in response to suppression of excitatory input to neurons in culture (Thiagarajan et al, 2005(Thiagarajan et al, , 2007Lee, 2012;Kim & Ziff, 2014) and cortical and brainstem sensory neurons in vivo (Goel et al, 2011;Jitsuki et al, 2011;Sarin et al, 2012). This homeostatic synaptic scaling is triggered by decreased Ca 2+ signaling (Thiagarajan et al, 2002;Kim & Ziff, 2014), and decreased activity of the Ca 2+ -dependent phosphatase, calcineurin, which normally dephosphorylates pSer845-GluA1 and enables endocytosis.…”

Differences in AMPA and GABAA/B receptor subunit expression between the chronically reorganized cortex and brainstem of adult squirrel monkeys

“…2002). This is followed by a subsequent phase of “developmental recapitulation” during which critical period like receptor expression (plasticity) is re-expressed in the deprived sensory neuraxis (Mowery and Garraghty, 2009; Mowery et al, 2011; Sarin et al, 2012). This phase could prime the cortex for the NMDA receptor-dependent stage of reorganization (Garraghty et al, 2006; Garraghty and Muja, 1996; Mowery et al, 2013; 2014 Myers et al, 2000).…”