NMDA receptor involvement in neuroplastic changes induced by neonatal capsaicin treatment in trigeminal nociceptive neurons.
نویسندگان
چکیده
NMDA receptor involvement in neuroplastic changes induced by neonatal capsaicin treatment in trigeminal nociceptive neurons. J. Neurophysiol. 78: 2799-2803, 1997. This study examines whether 1) the neonatal loss of C-fiber afferents results in neuroplastic changes in the mechanoreceptive field (RF) properties and spontaneous activity of nociceptive neurons in trigeminal subnucleus caudalis (medullary dorsal horn) of adult rats, and that 2) N-methyl--aspartic acid (NMDA) receptor mechanisms are involved in these neuroplastic changes. Compared with vehicle-treated (i.e., control, CON) rats, capsaicin-treated (CAP) rats showed a marked increase in neuronal spontaneous activity and RF size per se, but these neuroplastic changes could be significantly reduced by MK-801 (1 mg/kg, iv), a noncompetitive NMDA receptor antagonist; RF size and spontaneous activity remained unchanged in CON rats after MK-801 administration and in CAP rats after vehicle (saline, iv). Administration of 7-chlorokynurenic acid intrathecally (5 microgram/10 microliter), an antagonist of strychnine-insensitive glycine bindin sites on the NMDA receptor, also significantly reduced neuronal RF size and spontaneous activity in CAP rats, but not in CON rats. These data provide evidence that C-fiber afferents play a role in shaping the properties of nociceptive neurons and that the neuroplastic changes involve NMDA receptor mechanisms.
منابع مشابه
Nociceptive Neurons Induced By Neonatal Capsaicin Treatment in Trigeminal NMDA Receptor Involvement in Neuroplastic Changes
متن کامل
RAPID COMMUNICATION NMDA Receptor Involvement in Neuroplastic Changes Induced By Neonatal Capsaicin Treatment in Trigeminal Nociceptive Neurons
Chiang, Chen Yu, James W. Hu, and Barry J. Sessle. NMDA nociceptive neurons in trigeminal (V) subnucleus caudalis receptor involvement in neuroplastic changes induced by neonatal (medullary dorsal horn) of adult rats and 2) that NMDA capsaicin treatment in trigeminal nociceptive neurons. J. Neuroreceptor mechanisms are involved in these neuroplastic physiol. 78: 2799–2803, 1997. This study exam...
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عنوان ژورنال:
- Journal of neurophysiology
دوره 78 5 شماره
صفحات -
تاریخ انتشار 1997