neuropeptide-y and Spinal-Stenosis

The purpose of this observational study was to examine the association of protein and genetic biomarkers with pain and pain-related disability in individuals with axial low back pain undergoing epidural steroid injections.. Forty-eight adults with axial low back pain undergoing an epidural steroid injection were recruited from an academic medical center. Blood samples were assayed at baseline and follow-up for plasma proteins and functional single-nucleotide polymorphisms associated with pain. Data regarding pain and function were collected at baseline and follow-up. The characteristics of responders (defined as 50% improvement in pain score) and nonresponders were compared, and the association between response and baseline biomarkers was examined.. Thirty-five percent of subjects were responders to injection. Responders had lower baseline plasma levels of chondroitin sulfate 846 and higher neuropeptide Y and serotonin levels than nonresponders, and baseline neuropeptide Y level correlated with change in disability levels. In addition, subjects with the variant allele for the catechol-O-methyltransferase single-nucleotide polymorphism demonstrated increased odds of responding to the injection.. These data identify candidates who may have utility for patient selection for spinal procedures and provide support for exploration in prospective studies to assess and validate their predictive ability.

Topics: Adult; Biomarkers; Chondroitin Sulfates; Female; Follow-Up Studies; Humans; Injections, Epidural; Male; Middle Aged; Nerve Block; Neuropeptide Y; Prospective Studies; Serotonin; Spinal Stenosis

Our recent data revealed adrenergic sensitivity in chronically compressed dorsal root ganglion (DRG) of rats. As neuropeptide Y (NPY) is a common sympathetic co-transmitter, we investigated the effect of NPY on injured DRG neurons. The expression of NPY Y1 and Y2 receptors and the effect of NPY on chronically compressed DRG neurons were studied using in situ hybridization and extracellular single fiber recording in vitro, respectively. After DRG compression, the expression of Y1 receptor was distinctly increased in large and medium-sized DRG neurons, while Y2 receptor was increased in small DRG neurons. NPY inhibited both the spontaneous activity and the excitatory effect of norepinephrine in injured DRG A-neurons. The results suggest a possibility that NPY may inhibit the hyperexcitability of injured DRG A-neurons via increased Y1 receptor following chronic compression.

Topics: Action Potentials; Animals; Disease Models, Animal; Female; Ganglia, Spinal; In Situ Hybridization; Male; Nerve Compression Syndromes; Neurons, Afferent; Neuropeptide Y; Norepinephrine; Rats; Rats, Sprague-Dawley; Receptors, Neuropeptide Y; Spinal Stenosis