Organization of Sensory Input to the Nociceptive-Specific Cutaneous Trunk Muscle Reflex in Rat, an Effective Experimental System for Examining Nociception and Plasticity

• Type of Material: Article
• Authors: Jeffrey C. Petruska, University of Louisville; Darrel F. Barker, Stony Brook University; Sandra M. Garraway, Emory University; Robert Trainer, Stony Brook University; James W. Fransen, University of Louisville; Peggy A. Seidman, Stony Brook University; Roy G. Soto, Stony Brook University; Lorne M. Mendell, Stony Brook University; Richard D. Johnson, University of Florida
• Language: English
• Date: 2014-04-01
• Publisher: Wiley: 12 months
• Publication Version: Author Accepted Manuscript (After Peer Review)
• Copyright Statement: © 2013 Wiley Periodicals, Inc.
• Final Published Version (URL): http://dx.doi.org/10.1002/cne.23461
• Title of Journal or Parent Work: Journal of Comparative Neurology
• ISSN: 0021-9967
• Volume: 522
• Issue: 5
• Start Page: 1048
• End Page: 1071
• Grant/Funding Information: This work was supported in part by the National Institutes of Health (NS080091 – JCP; NS016996 – LMM; NS027511 – RDJ; P30GM103507 (PI – S.R. Whittemore) supporting the KSCIRC Core facilities); the Florida Brain and Spinal Cord Injury Rehabilitation Trust Fund (RDJ); The Christopher and Dana Reeve Foundation (LMM); the UofL Dept. of Neurological Surgery (JCP); the Kentucky Spinal Cord and Head Injury Research Trust (09-12A and 10-10 to JCP); the SUNY Stony Brook Department of Anesthesiology (Chair Peter Glass supporting RT, RGS, PAS); and the University of Florida Medical Guild (JCP).
• Keywords: SPINAL-CORD-INJURY; NEUROTROPHIC FACTOR; pharmacology; NEUROPATHIC PAIN; pain; PRIMARY AFFERENT NEURONS; ADULT-RATS; Neurosciences & Neurology; spinal cord; BEHAVIORAL EVIDENCE; sensory neurons; RECEPTOR MESSENGER-RNA; plasticity; Neurosciences; anesthesiology; Zoology; LAMINA-II; animal models; Life Sciences & Biomedicine; Science & Technology; DORSAL-ROOT GANGLION; NERVE GROWTH-FACTOR
• Research Categories: Biology, Neuroscience; Biology, Physiology; Biology, Anatomy

Abstract

Detailed characterization of neural circuitries furthers our understanding of how nervous systems perform specific functions and allows the use of those systems to test hypotheses. We have characterized the sensory input to the cutaneous trunk muscle (CTM; also cutaneus trunci [rat] or cutaneus maximus [mouse]) reflex (CTMR), which manifests as a puckering of the dorsal thoracolumbar skin and is selectively driven by noxious stimuli. CTM electromyography and neurogram recordings in naïve rats revealed that CTMR responses were elicited by natural stimuli and electrical stimulation of all segments from C4 to L6, a much greater extent of segmental drive to the CTMR than previously described. Stimulation of some subcutaneous paraspinal tissue can also elicit this reflex. Using a selective neurotoxin, we also demonstrate differential drive of the CTMR by trkA-expressing and nonexpressing small-diameter afferents. These observations highlight aspects of the organization of the CTMR system that make it attractive for studies of nociception and anesthesiology and plasticity of primary afferents, motoneurons, and the propriospinal system. We use the CTMR system to demonstrate qualitatively and quantitatively that experimental pharmacological treatments can be compared with controls applied either to the contralateral side or to another segment, with the remaining segments providing controls for systemic or other treatment effects. These data indicate the potential for using the CTMR system as both an invasive and a noninvasive quantitative assessment tool providing improved statistical power and reduced animal use.