Cellular neuroscienceBDNF and learning: Evidence that instrumental training promotes learning within the spinal cord by up-regulating BDNF expression
Section snippets
Animal subjects
Adult male Sprague–Dawley rats (Harlan, Houston, TX, USA), 90–100 days old, were individually-housed, maintained on a 12-h light/dark cycle, and given ad libitum access to food and water. The experiments adhered to the NIH guidelines for the care and use of animals and were approved by the University Laboratory Animal Care Committee at Texas A&M University. All experiments employed a group size (n) of 6, taking care to minimize the number of animals used and their suffering.
Spinal transection
Surgery was
Instrumental training
Shock was applied using s.c. electrodes to elicit a flexion of the ankle joint, i.e. a decrease of the angle between the tibia and the foot. As in prior studies, e.g. (Grau et al., 1998), master rats learned to hold the leg in a flexed position, yielding an increase in response duration over time (Fig. 2). Yoked subjects, that receive the same amount of shock independent of leg position, did not exhibit an increase in response duration, our index of instrumental learning. Instead, they appeared
Discussion
We have used a quantitative instrumental learning paradigm to determine the involvement of the BDNF systems on the mechanisms of learning in the spinal cord. Instrumental training was conducted after a complete spinal cord transection that was performed to eliminate any influence from suprasegmental centers on the motor behavior. Therefore, any new motor learning would be related to molecular adaptations in the neural circuits remaining in the spinal cord below the lesion. Animals that learned
Acknowledgments
This work was supported by NIH awards NS41548 (J.W.G.), NS45804 (F.G.P.), and NS16333 (V.R.E.) and by the Craig H. Nielsen Foundation.
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2021, Experimental NeurologyCitation Excerpt :While Lovett-Barr et al. (Lovett-Barr et al., 2012) extended these findings in rats with incomplete SCI and showed that neurochemical changes in BDNF and tyrosine kinase B occur following AIH exposure in both respiratory and non-respiratory motor nuclei that correspond to functional improvements in both breathing and locomotion. Upregulation of BDNF mRNA via motor training (exercise) also is associated with functional recovery after SCI (Gómez-Pinilla et al., 2007), and training in rats with SCI increases spinal BDNF expression (Huie et al., 2012). Other rat SCI models show that locomotor training and exercise also trigger BDNF synthesis within the spinal cord (Ying et al., 2008).
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2021, Experimental NeurologyCitation Excerpt :Using flexion reflex conditioning in spinal rats, it was demonstrated that nociceptive electrical stimulation could prevent task-related training effects on reflex conditioning (Ferguson et al., 2006) by a glia-dependent mechanism (Grau et al., 2014; Huie et al., 2012a). Conversely, training could prevent the disruptive effect of nociceptive inputs on reflex conditioning (Crown and Grau, 2001) by a brain-derived neurotrophic factor (BDNF)-dependent mechanism (Gómez-Pinilla et al., 2007; Huie et al., 2012b). In addition to the contribution of glia and BDNF to both nociceptive and recovery processes, the expression of the cation-chloride cotransporter type 2 (KCC2) is pivotal in chloride homeostasis responsible for GABA inhibitory transmission and is reduced after SCI (Boulenguez et al., 2010).
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2020, Experimental NeurologyMemory-enhancing effects of 7,3′,4′-trihydroxyisoflavone by regulation of cholinergic function and BDNF signaling pathway in mice
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2019, Infant Behavior and DevelopmentCitation Excerpt :Here we focus on brain-derived neurotrophic factor (Bdnf), a major player in CNS plasticity and particularly in developmental processes, including regulation of critical periods (Gianfranceschi et al., 2003; Hanover, Huang, Tonegawa, & Stryker, 1999; Huang et al., 1999). This gene is a known target of environmentally-induced epigenetic modifications in the brain (Blaze & Roth, 2017; Doherty, Forster, & Roth, 2016; Lubin, Roth, & Sweatt, 2008; Ma et al., 2009; Onishchenko, Karpova, Sabri, Castrén, & Ceccatelli, 2008; Roth, Lubin, Funk, & Sweatt, 2009; Ventskovska, Porkka‐Heiskanen, & Karpova, 2015), and has been implicated in adult spinal learning (Gómez-Pinilla et al., 2007; Huie et al., 2012) and in locomotor improvement in response to training and exercise following transection (Joseph, Tillakaratne, & de Leon, 2012; Macias et al., 2009). In addition, overexpression of Bdnf alone has been associated with improved locomotor outcomes in spinal-transected animals (Boyce, Park, Gage, & Mendell, 2012; Ziemlińska et al., 2014).