Open AccessThermo-dependence of noxious mechanical heterotopic stimulation-dependent modulation of the spinal dorsal horn response to somatosensory stimulation
Author(s) -
J. Meléndez-Gallardo,
Antonio Eblén-Zajjur
Publication year - 2018
Publication title -
journal of integrative neuroscience
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.336
H-Index - 33
eISSN - 1757-448X
pISSN - 0219-6352
DOI - 10.3233/jin-180076
Subject(s) - diffuse noxious inhibitory control , spinal cord , noxious stimulus , nociception , stimulation , somatosensory system , anesthesia , lumbar spinal cord , medicine , sural nerve , neuroscience , sensation , neuropathic pain , sensory system , nociceptor , anatomy , psychology , receptor
Despite the frequent clinical hyper- or hypothermia cases, thermal-dependence of the endogenous pain modulation system at the spinal cord is not well understood. We evaluate spinal dorsal horn neuronal network responses during mechanical heterotopic noxious stimuli (HNS) at three different body temperatures (34; 37 or 40°C) by measuring lumbar cord dorsum potentials activated by electrical stimulation of the ipsilateral sural nerve in adult thiopental anesthetized rats. A noxious clamp was applied randomly to the tail, right hindpaw, right forepaw, muzzle and left forepaw. HNS induced a decrease of the N wave amplitude and duration at 37°C. This effect was reduced at 40°C for both amplitude (-18.2% for 37-40°C; P<0.0005) and duration (-16.4% for 37-40°C; P<0.0001). P wave did not show neither amplitude nor duration changes at neither 3 tested temperatures. Clinical range changes of temperature could modify pain sensation, moreover, hyperthermia increases nociceptive sensory input to dorsal horn, and could exacerbate pain sensation in individuals with fever.