Are there long-term changes in the basal or evoked Fos expression in the dorsal horn of the spinal cord of the mononeuropathic rat?

Pain ◽  
1999 ◽  
Vol 80 (1) ◽  
pp. 347-357 ◽  
Author(s):  
Gwénaëlle Catheline ◽  
Stéphanie Le Guen ◽  
Prisca Honoré ◽  
Jean-Marie Besson
Keyword(s):  
Spinal Cord ◽  
Dorsal Horn ◽  
Long Term Changes ◽  
Fos Expression

Elimination of rat spinal neurons expressing neurokinin 1 receptors reduces bladder overactivity and spinal c-fos expression induced by bladder irritation

2005 ◽  
Vol 288 (3) ◽  
pp. F466-F473 ◽  
Author(s):  
Satoshi Seki ◽  
Kristin A. Erickson ◽  
Masako Seki ◽  
Osamu Nishizawa ◽  
Yasuhiko Igawa ◽  
...  
Keyword(s):  
Spinal Cord ◽  
Dorsal Horn ◽  
Intrathecal Administration ◽  
Superficial Layer ◽  
Sprague Dawley ◽  
Intrathecal Catheter ◽  
Micturition Reflex ◽  
Nociceptive Responses ◽  
Fos Expression ◽  
Neurokinin 1

Substance P (SP) binding to neurokinin 1 receptors (NK1R) in the spinal cord reportedly plays an important role in the micturition reflex as well as in nociceptive responses. We therefore investigated the effect of ablation of NK1R-expressing neurons in the spinal cord using saporin, a ribosome-inactivating protein, conjugated with [Sar9, Met (O2)11]SP, a specific ligand of NK1R (SSP-saporin), on the micturition reflex in rats. In female Sprague-Dawley rats, SSP-saporin (1.0 or 1.5 μM) or saporin (1.5 μM) only was injected through an intrathecal catheter implanted at the L6-S1 level of the spinal cord. Three weeks after intrathecal administration of SSP-saporin, NK1R immunoreactivity in lamina I of the spinal cord was significantly reduced, but cystometric parameters in awake rats were not altered. Instillation of capsaicin (15 μM) into the bladder of normal rats induced bladder overactivity. This response to capsaicin was significantly suppressed in SSP-saporin-treated animals. SSP-saporin treatment also decreased c- fos expression in the dorsal horn of the spinal cord induced by instillation of capsaicin into the bladder. These data indicate that NK1R-expressing neurons in the superficial layer of the dorsal horn play an important role in transmission of nociceptive afferent information from the bladder to induce bladder overactivity and spinal c- fos expression elicited by bladder irritation. Toxin-induced damage of NK1R-expressing neurons in the lumbosacral spinal cord may provide an effective modality for treating overactivity and/or nociceptive responses in the bladder without affecting normal micturition.

Long-term changes in expressions of spinal glutamate transporters after spinal cord injury

2011 ◽  
Vol 1389 ◽  
pp. 194-199 ◽  
Author(s):  
Youngkyung Kim ◽  
Young-Keun Park ◽  
Hwi-young Cho ◽  
Junesun Kim ◽  
Young Wook Yoon
Keyword(s):  
Spinal Cord ◽  
Spinal Cord Injury ◽  
Glutamate Transporters ◽  
Cord Injury ◽  
Long Term Changes

Serotonin Increases the Incidence of Primary Afferent-Evoked Long-Term Depression in Rat Deep Dorsal Horn Neurons

2001 ◽  
Vol 85 (5) ◽  
pp. 1864-1872 ◽  
Author(s):  
Sandra M. Garraway ◽  
Shawn Hochman
Keyword(s):  
Spinal Cord ◽  
Dorsal Horn ◽  
Long Term Potentiation ◽  
Neonatal Rat ◽  
Long Term Depression ◽  
Primary Afferent ◽  
Dorsal Horn Neurons ◽  
Sensory Evoked ◽  
Synaptic Responses

5-hydroxytryptamine (5-HT) is released in spinal cord by descending systems that modulate somatosensory transmission and can potently depress primary afferent-evoked synaptic responses in dorsal horn neurons. Since primary afferent activity-induced long-term potentiation (LTP) may contribute to central sensitization of nociception, we studied the effects of 5-HT on the expression of sensory-evoked LTP and long-term depression (LTD) in deep dorsal horn (DDH) neurons. Whole cell, predominantly current clamp, recordings were obtained from DDH neurons in transverse slices of neonatal rat lumbar spinal cord. The effect of 5-HT on dorsal-root stimulation-evoked synaptic responses was tested before, during, or after high-frequency conditioning stimulation (CS). In most cells (80%), 5-HT caused a depression of the naı̈ve synaptic response. Even though 5-HT depressed evoked responses, CS in the presence of 5-HT was not only still capable of inducing LTD but also increased its incidence from 54% in controls to 88% ( P < 0.001). Activation of ligands selective for 5-HT1A/1B and 5-HT1B, but not 5-HT2A/2C or 5-HT3receptors, best reproduced these actions. 5-HT also potently depressed postconditioning synaptic responses regardless of whether the induced plasticity was LTP or LTD. Our results demonstrate that in addition to depressing the amplitude of evoked sensory input, 5-HT can also control the direction of its long-term modifiability, favoring the expression of LTD. These findings demonstrate cellular mechanisms that may contribute to the descending serotonergic control of nociception.

Role of NO in modulating neuronal activity in superficial dorsal horn of spinal cord during exercise pressor reflex

2002 ◽  
Vol 283 (3) ◽  
pp. H1012-H1018 ◽  
Author(s):  
Jianhua Li ◽  
Jere H. Mitchell
Keyword(s):  
Spinal Cord ◽  
Dorsal Horn ◽  
Pressor Response ◽  
Triceps Surae ◽  
Superficial Dorsal Horn ◽  
Exercise Pressor Reflex ◽  
Fos Protein ◽  
Static Contraction ◽  
Pressor Reflex ◽  
Fos Expression

Static contraction of hindlimb skeletal muscle in cats induces a reflex pressor response. The superficial dorsal horn of the spinal cord is the major site of the first synapse of this reflex. In this study, static contraction of the triceps surae muscle was evoked by electrical stimulation of the tibial nerve for 2 min in anesthetized cats (stimulus parameters: two times motor threshold at 30 Hz, 0.025-ms duration). Ten stimulations were performed and 1-min rest was allowed between stimulations. Muscle contraction caused a maximal increase of 32 ± 5 mmHg in mean arterial pressure (MAP), which was obtained from the first three contractions. Activated neurons in the superficial dorsal horn were identified by c-Fos protein. Distinct c-Fos expression was present in the L6-S1 level of the superficial dorsal horn ipsilateral to the contracting leg (88 ± 14 labeled cells per section at L7), whereas only scattered c-Fos expression was observed in the contralateral superficial dorsal horn (9 ± 2 labeled cells per section, P < 0.05 compared with ipsilateral section). A few c-Fos-labeled cells were found in control animals (12 ± 5 labeled cells per section, P < 0.05 compared with stimulated cats). Furthermore, double-labeling methods demonstrated that c-Fos protein coexisted with nitric oxide (NO) synthase (NOS) positive staining in the superficial dorsal horn. Finally, an intrathecal injection of an inhibitor of NOS, N-nitro-l-arginine methyl ester (5 mM), resulted in fewer c-Fos-labeled cells (58 ± 12 labeled cells per section) and a reduced maximal MAP response (20 ± 3 mmHg, P < 0.05). These results suggest that the exercise pressor reflex induced by static contraction is mediated by activation of neurons in the superficial dorsal horn and that formation of NO in this region is involved in modulating the activated neurons and the pressor response to contraction.

Sign in / Sign up

Export Citation Format

Share Document