Light delays synaptic deafferentation and potentiates the survival of axotomized retinal ganglion cells.
Knowledge of the cellular mechanism underlying the therapeutic effect of stimulation and the optimal doses of such stimulation to maximize neuronal recovery is essential to guide clinical practice in neural rehabilitation. Using hamsters, we transected the optic nerve to demonstrate how light stimulation affects neuronal recovery. The c-fos protein was used as a neuronal connectivity marker. Here we show that: (a) in addition to cell death, a population of cells undergoes synaptic deafferentation and (b) light stimulation delays cell death and deafferentation. Among the three rearing conditions studied (6:18LD, 12:12LD, and 18:6LD), the 12:12LD condition appears to be the one achieving the optimal therapeutic effect. This study provides a solid base in the understanding of the neuroanatomical changes after traumatic brain injury and the need to establish an optimal level and timing for the environmental stimulation.
So
Kwok-Fai
KF
Department of Anatomy, The University of Hong Kong, Hong Kong SAR, PR China.
Ho
Lisa S H
LS
Tay
David K C
DK
Lee
Tatia M C
TM
D000818:Animals; D019771:Axotomy; D016923:Cell Death / Q000502:physiology / Q000528:radiation effects; D002470:Cell Survival / Q000502:physiology / Q000528:radiation effects; D006224:Cricetinae; D004307:Dose-Response Relationship, Radiation; D008027:Light; D008297:Male; D008647:Mesocricetus; D009475:Neurons, Afferent / Q000502:physiology* / Q000528:radiation effects; D017711:Nonlinear Dynamics; D009900:Optic Nerve / Q000502:physiology; D016760:Proto-Oncogene Proteins c-fos / Q000096:biosynthesis / Q000502:physiology; D012165:Retinal Ganglion Cells / Q000502:physiology* / Q000528:radiation effects; D013569:Synapses / Q000502:physiology* / Q000528:radiation effects
D016760:Proto-Oncogene Proteins c-fos