Physical exercise enhances adult cortical plasticity in a neonatal rat model of hypoxic-ischemic injury: Evidence from BOLD-fMRI and electrophysiological recordings

Publication date: Available online 12 December 2018Source: NeuroImageAuthor(s): Sun Young Chae, Jun Ho Jang, Geun Ho Im, Ji-Hyun Jeong, Won-Beom Jung, Sukjin Ko, Hyesoo Jie, Ji Hye Kim, Yun Sil Chang, Seungsoo Chung, Ki-Soo Kim, Jung Hee LeeAbstractNeuroplasticity is considered essential for recovery from brain injury in developing brains. Recent studies indicate that it is especially effective during early postnatal development and during the critical period. The current study used functional magnetic resonance imaging (fMRI) and local field potential (LFP) electrophysiological recordings in rats that experienced neonatal hypoxic-ischemic (HI) injury during the critical period to demonstrate that physical exercise (PE) can improve cortical plasticity even when performed during adulthood, after the critical period. We investigated to what extent the blood oxygen level-dependent (BOLD)-fMRI responses were increased in the contralesional spared cortex, and how these increases were related to the LFP electrophysiological measurements and the functional outcome. The balance of excitation and inhibition was assessed by measuring excitatory and inhibitory postsynaptic currents in stellate cells in the primary somatosensory (S1) cortex, which was compared with the BOLD-fMRI responses in the contralesional S1 cortex. The ratio of inhibitory postsynaptic current (IPSC) to excitatory postsynaptic current (EPSC) at the thalamocortical (TC) input to the spared S1 cortex was significantly...
Source: NeuroImage - Category: Neuroscience Source Type: research