title: Expression of the immediate-early gene egr-1 and substance P in the spinal cord following locomotor training in adult rats.
abstract: The immediate-early gene egr-1 has been shown to have an increased expression during long-term potentiation (LTP). High frequency electrical stimulation induces an increase in such expression in the dorsal horn of the spinal cord. However, evidence demonstrating the activation of this gene in the spinal cord and its relationship with LTP is still scarce. The substance P (SP) has also been associated with LTP in the dorsal horn of the spinal cord following high frequency stimulation. Here we evaluated the expression of both Egr-1 and SP in the sacrolumbar area of the spinal cord after locomotor training in adult rats. Increased neuronal Egr-1 expression was found in the spinal cord sections in rats that underwent locomotor training, especially in laminae IV and X across L3-S4 levels (p<0.05). Conversely, SP expression in synaptic terminals was not altered in the abovementioned regions. Our results suggest that locomotor training activates mechanisms in a similar way to LTP, and is involved in the synaptic plasticity in the spinal cord. The results also indicate that variations in the training protocol influence Egr-1 expression. Such events appear not to be directly influenced by SP, which suggests a plastic process that differs from those triggered by nociceptive stimuli.
authors.affiliation: Department of Morphology, Center for Biosciences, Federal University of Rio Grande do Norte, Natal/RN, Brazil. aclnunes@gmail.com
authors.forename: Ana Carla L
authors.initials: AC
authors.lastname: Nunes
authors.forename: Renata B
authors.initials: RB
authors.lastname: Duarte
authors.forename: Twyla B
authors.initials: TB
authors.lastname: Sousa
authors.forename: José Ronaldo
authors.initials: JR
authors.lastname: dos Santos
authors.forename: Marco Aurélio M
authors.initials: MA
authors.lastname: Freire
authors.forename: Miriam Stela Maris O
authors.initials: MS
authors.lastname: Costa
mesh_terms: D000375:Aging; D000818:Animals; D051766:Early Growth Response Protein 1 / Q000378:metabolism*; D007150:Immunohistochemistry; D008159:Lumbar Vertebrae; D009473:Neuronal Plasticity; D009474:Neurons / Q000378:metabolism; D010805:Physical Conditioning, Animal / Q000502:physiology*; D020671:Posterior Horn Cells / Q000378:metabolism; D051381:Rats; D017208:Rats, Wistar; D012447:Sacrum; D013116:Spinal Cord / Q000378:metabolism*; D013373:Substance P / Q000378:metabolism*
chemical_list: D051766:Early Growth Response Protein 1; C486110:Egr1 protein, rat; D013373:Substance P