TY - JOUR
T1 - L-Dopa effect on frequency-dependent depression of the H-reflex in adult rats with complete spinal cord transection
AU - Liu, Hao
AU - Skinner, Robert D.
AU - Arfaj, Ahmad
AU - Yates, Charlotte
AU - Reese, Nancy B.
AU - Williams, Keith
AU - Garcia-Rill, Edgar
N1 - Funding Information:
This study was supported by NIH-NCRR Grant P20 RR020146 to the Center for Translational Neuroscience.
PY - 2010/10/30
Y1 - 2010/10/30
N2 - This study investigated whether l-dopa (DOPA), locomotor-like passive exercise (Ex) using a motorized bicycle exercise trainer (MBET), or their combination in adult rats with complete spinal cord transection (Tx) preserves and restores low frequency-dependent depression (FDD) of the H-reflex. Adult Sprague-Dawley rats (n= 56) transected at T8-9 had one of five treatments beginning 7 days after transection: Tx (transection only), Tx. +. Ex, Tx. +. DOPA, Tx. +. Ex. +. DOPA, and control (Ctl, no treatment) groups. After 30 days of treatment, FDD of the H-reflex was tested. Stimulation of the tibial nerve at 0.2, 1, 5, and 10. Hz evoked an H-reflex that was recorded from plantar muscles of the hind paw. No significant differences were found at the stimulation rate of 1. Hz. However, at 5. Hz, FDD of the H-reflex in the Tx. +. Ex, Tx. +. DOPA and Ctl groups was significantly different from the Tx group (p< 0.01). At 10. Hz, all of the treatment groups were significantly different from the Tx group (p< 0.01). No significant difference was identified between the Ctl and any of the treatment groups. These results suggest that DOPA significantly preserved and restored FDD after transection as effectively as exercise alone or exercise in combination with DOPA. Thus, there was no additive benefit when DOPA was combined with exercise.
AB - This study investigated whether l-dopa (DOPA), locomotor-like passive exercise (Ex) using a motorized bicycle exercise trainer (MBET), or their combination in adult rats with complete spinal cord transection (Tx) preserves and restores low frequency-dependent depression (FDD) of the H-reflex. Adult Sprague-Dawley rats (n= 56) transected at T8-9 had one of five treatments beginning 7 days after transection: Tx (transection only), Tx. +. Ex, Tx. +. DOPA, Tx. +. Ex. +. DOPA, and control (Ctl, no treatment) groups. After 30 days of treatment, FDD of the H-reflex was tested. Stimulation of the tibial nerve at 0.2, 1, 5, and 10. Hz evoked an H-reflex that was recorded from plantar muscles of the hind paw. No significant differences were found at the stimulation rate of 1. Hz. However, at 5. Hz, FDD of the H-reflex in the Tx. +. Ex, Tx. +. DOPA and Ctl groups was significantly different from the Tx group (p< 0.01). At 10. Hz, all of the treatment groups were significantly different from the Tx group (p< 0.01). No significant difference was identified between the Ctl and any of the treatment groups. These results suggest that DOPA significantly preserved and restored FDD after transection as effectively as exercise alone or exercise in combination with DOPA. Thus, there was no additive benefit when DOPA was combined with exercise.
KW - DOPA
KW - Exercise
KW - H-reflex
KW - Hyperreflexia
KW - Low frequency-dependent depression
KW - Spasticity
KW - Spinal cord injury
UR - http://www.scopus.com/inward/record.url?scp=77957661913&partnerID=8YFLogxK
U2 - 10.1016/j.brainresbull.2010.07.005
DO - 10.1016/j.brainresbull.2010.07.005
M3 - Article
C2 - 20637842
AN - SCOPUS:77957661913
SN - 0361-9230
VL - 83
SP - 262
EP - 265
JO - Brain Research Bulletin
JF - Brain Research Bulletin
IS - 5
ER -