Release of neurotransmitters in the spinal cord will be correlated with changes in modulation of activity in nociceptive transmission cells. Microdialysis probes will be placed in the spinal cord dorsal horn of anesthetized cats and monkeys to sample neurotransmitter release. Nociceptive projection cells within the sampling area of the probe will be recorded from extracellularly. Release and modulation will be evoked by electric stimulation of supraspinal sites including nucleus raphe magnus, periaqueductal gray, locus coeruleus, nucleus Kolliker fuse and sensory motor cortex. These sites were chosen for their diverse types of modulatory effects. Glutamate, aspartate, GABA and glycine as well as serotonin and/or norepinephrine will be measured in all dialysis samples using HPLCs with fluorescence and electrochemical detection. Administration of agonists and antagonists through the probes will respectively mimic and block the effects of supraspinal stimulation. Selective spinal lesions will result in loss of specific components of the descending modulation and loss of some neurotransmitter release. These experiments will allow us to match specific neurotransmitters or ratios of neurotransmitters with specific types of modulation of ascending somatosensory information. Taken together, results from these experiments will increase our understanding of sensory processing in the spinal cord and pain processing in particular.

Project Start
Project End
Budget Start
Budget End
Support Year
19
Fiscal Year
1993
Total Cost
Indirect Cost
Name
University of Texas Medical Br Galveston
Department
Type
DUNS #
041367053
City
Galveston
State
TX
Country
United States
Zip Code
77555
Carter, Michael W; Johnson, Kathia M; Lee, Jun Yeon et al. (2016) Comparison of Mechanical Allodynia and Recovery of Locomotion and Bladder Function by Different Parameters of Low Thoracic Spinal Contusion Injury in Rats. Korean J Pain 29:86-95
Hammell, D C; Zhang, L P; Ma, F et al. (2016) Transdermal cannabidiol reduces inflammation and pain-related behaviours in a rat model of arthritis. Eur J Pain 20:936-48
Young, E E; Bryant, C D; Lee, S E et al. (2016) Systems genetic and pharmacological analysis identifies candidate genes underlying mechanosensation in the von Frey test. Genes Brain Behav 15:604-15
Yuan, Su-Bo; Ji, Guangchen; Li, Bei et al. (2015) A Wnt5a signaling pathway in the pathogenesis of HIV-1 gp120-induced pain. Pain 156:1311-9
Ji, Guangchen; Li, Zhen; Neugebauer, Volker (2015) Reactive oxygen species mediate visceral pain-related amygdala plasticity and behaviors. Pain 156:825-36
Neugebauer, Volker (2015) Amygdala pain mechanisms. Handb Exp Pharmacol 227:261-84
Hassler, Shayne N; Johnson, Kathia M; Hulsebosch, Claire E (2014) Reactive oxygen species and lipid peroxidation inhibitors reduce mechanical sensitivity in a chronic neuropathic pain model of spinal cord injury in rats. J Neurochem 131:413-7
Ji, Guangchen; Neugebauer, Volker (2014) CB1 augments mGluR5 function in medial prefrontal cortical neurons to inhibit amygdala hyperactivity in an arthritis pain model. Eur J Neurosci 39:455-66
Medina, Georgina; Ji, Guangchen; Gr├ęgoire, St├ęphanie et al. (2014) Nasal application of neuropeptide S inhibits arthritis pain-related behaviors through an action in the amygdala. Mol Pain 10:32
Yowtak, June; Wang, Jigong; Kim, Hee Young et al. (2013) Effect of antioxidant treatment on spinal GABA neurons in a neuropathic pain model in the mouse. Pain 154:2469-76

Showing the most recent 10 out of 585 publications