Cortical Presynaptic Control of Dorsal Horn C–Afferents in the Rat

• DOI: 10.1371/journal.pone.0069063
• Publication Date: 2013-07-30T21:04:02Z
• Authors: Yunuen Moreno-López; Jimena Pérez-Sánchez; Guadalupe Martíne...; Miguel Condés-Lara; Gerardo Rojas-Piloni
• Keywords: Tetanic stimulation

Lamina 5 sensorimotor cortex pyramidal neurons project to the spinal cord, participating in modulation of several modalities information transmission. A well-studied mechanism by which corticospinal projection modulates sensory is primary afferent depolarization, has been characterized fast muscular and cutaneous, but not slow-conducting nociceptive skin afferents. Here we investigated whether inhibition information, produced activation cortex, involves a direct presynaptic C In anaesthetized male Wistar rats, analyzed effects on post tetanic potentiation (PTP) paired pulse ratio (PPR) dorsal horn field potentials evoked C–fiber stimulation sural (SU) sciatic (SC) nerves. We also explored time course excitability changes afferents cortical stimulation. observed that development PTP was completely blocked when C-fiber with addition, topical administration bicuculline (BIC) reduction amplitude responses, as well an increase PPR. Furthermore, increases intraspinal fiber terminals, stimulation, were indicative depolarization. Topical BIC cord neuronal responses Dorsal responding exhibited peripheral receptive responded cutaneous myelinated fibers. Our results suggest due part C–fibers means GABAergic inhibitory interneurons.