The expression of Fos-labeled spinal neurons in response to colorectal distension is enhanced after chronic spinal cord transection in the rat
Section snippets
Experimental procedures
Experiments were performed at 1 day or 30 days post-surgery in 55 male Wistar rats (Charles River; Wilmington, MA, USA) ranging in weight from 340 to 500 g. All procedures were approved by the University of Oklahoma Health Sciences Center Institutional Animal Care and Use Committee, and conformed with the National Institutes of Health guide for the care and use of laboratory animals. All efforts were made to minimize animal suffering and to minimize the number of animals necessary to produce
Total numbers of Fos-labeled neurons for 1 day and 30 day groups
Neurons demonstrating Fos-like immunoreactivity were analyzed for spinal segments L5–S2. Fos-labeled neurons were most densely located between the segments of L6 and the rostral end of S1 with the fewest number of labeled neurons in the S2 segment. Sample sections of tissue which show the locations of labeled neurons in 1 day and 30 day rats are illustrated in Fig. 2, Fig. 3, respectively. The five regions of the spinal cord that were analyzed are also designated in these figures. Group means
Discussion
The purpose of this study was to examine changes in neuronal activation in response to CRD in an acute and chronic model of spinal cord injury. Of particular interest were potential changes in chronic lesioned animals as an indicator of plasticity that ultimately results in the myriad functional changes that occur following spinal cord injury. Our results indicate that approximately three times as many neurons respond to CRD after chronic spinal cord injury compared to neurally intact animals.
Conclusions
In summary, we found a profound increase in the number of neurons expressing Fos in response to CRD following a chronic spinal cord injury. This response may represent a functional anatomical reorganization of spinal cord circuitry that ultimately underlies the functional alterations associated with chronic spinal cord injury in humans.
Acknowledgements
This research was supported by Grant #9507884S from the Oklahoma Affiliate of the American Heart Association, and by Grant HD38019 from NIH.
References (38)
- et al.
The central organization of the vagus nerve innervating the colon of the rat
Gastroenterology
(1993) - et al.
Co-localization of substance P and dopamine β-hydroxylase with growth-associated protein-43 is lost caudal to a spinal cord transection
Neuroscience
(1999) - et al.
Expression of c-fos protein in lumbosacral spinal cord in response to vaginocervical stimulation in rats
Neurosci. Lett.
(1992) - et al.
Sprouting of primary afferent fibers after spinal cord transection in the rat
Neuroscience
(1998) - et al.
Spinal and hindbrain structures involved in visceroception and visceronociception as revealed by the expression of Fos, Jun and Krox-24 proteins
Neuroscience
(1993) - et al.
Colorectal distension as a noxious visceral stimulus: physiologic and pharmacologic characterization of pseudaffective reflexes in the rat
Brain Res.
(1988) - et al.
Cardiovascular consequences of loss of supraspinal control of the sympathetic nervous system after spinal cord injury
Arch. Phys. Med. Rehabil.
(2000) - et al.
Fos-like proteins in the lumbosacral spinal cord following noxious and non-noxious colorectal distension in the rat
Pain
(1992) - et al.
Differential expression of c-fos and c-jun in two regions of the rat spinal cord following noxious colorectal distension
Neurosci. Lett.
(1993) - et al.
Attenuation of c-Fos expression in the rat lumbosacral cord by morphine or tramadol following noxious colorectal distension
Brain Res.
(1995)
Autonomic dysreflexia and its urological implications: a review
J. Urol.
Spinal expression of Fos to colorectal distension is enhanced 30 days, but not 1 day, after spinal transection
Soc. Neurosci. Abst.
Expression of c-fos-like protein as a marker for neuronal activity following noxious stimulation in the rat
J. Comp. Neurol.
Effect of capsaicin on the micturition reflex in normal and chronic spinal cord-injured cats
Am. J. Physiol.
Spinal projections of pelvic visceral afferents of the rat: a calcitonin gene-related peptide (CGRP) immunohistochemical study
J. Comp. Neurol.
Cardiac and abdominal vagal afferent inhibition of primate T9–S1 spinothalamic cells
Am. J. Physiol.
Visceral and somatic afferent convergence onto neurons near the central canal in the sacral spinal cord of the cat
J. Neurophysiol.
Induction of c-fos-like protein in spinal cord neurons following sensory stimulation
Nature
Cited by (24)
Sensory spinal interoceptive pathways and energy balance regulation
2023, Molecular MetabolismCombining Constitutively Active Rheb Expression and Chondroitinase Promotes Functional Axonal Regeneration after Cervical Spinal Cord Injury
2017, Molecular TherapyCitation Excerpt :In our previous studies, we were able to assess synapse formation by placing the PNG bridge that lies outside the spinal cord on a hook electrode to specifically stimulate regenerating axons within the graft. We and others have used the immediate-early gene c-Fos as a marker of transsynaptic neuronal activation.10,13,26,27 We counted the number of c-Fos neurons in host spinal cord after electrical stimulation of the PNG as an indicator of neurons that were synapsed upon by axons that grew out of the PNG.
The pattern of Fos expression in the spinal dorsal horn following acute noxious mechanical stimulation of bone
2008, European Journal of PainCitation Excerpt :Fos expression is greatest in the superficial dorsal horn following brief noxious mechanical stimulation of cutaneous tissues (Dai et al., 2001; Jinks et al., 2002a; Jinks et al., 2002b; Leah et al., 1992; Rahman et al., 2002; Shimode et al., 2003). In contrast, Fos expression is greatest in the deep dorsal horn following noxious mechanical stimulation of visceral tissues (Birder and de Groat, 1992; Birder and de Groat, 1993; Cruz et al., 1994; Ghanima et al., 2002; Ghanima et al., 2000; Landrum et al., 2002; Tong et al., 2003; Traub and Murphy, 2002; Traub et al., 1995; Traub et al., 2002). This highlights the notion that spinal mechanisms that mediate pain of cutaneous and visceral origin are different.
Prolonged nociceptive responses to hind paw formalin injection in rats with a spinal cord injury
2008, Neuroscience LettersExpansion of formalin-evoked Fos-immunoreactivity in rats with a spinal cord injury
2007, Neuroscience Research