Kevin C. Chan1,2, Yu-Xiang Liang3, Rutledge G. Ellis-Behnke3, Kwok-fai So3, Ed X. Wu1,2
1Laboratory of Biomedical Imaging and Signal Processing, The University of Hong Kong, Hong Kong SAR, China; 2Department of Electrical and Electronic Engineering, The University of Hong Kong, Hong Kong SAR, China; 3Department of Anatomy, The University of Hong Kong, Hong Kong SAR, China
This study aims to employ in vivo proton magnetic resonance spectroscopy (1H MRS) to monitor longitudinally the metabolic changes in the superior colliculi (SC) following transections of the optic tract in adult hamsters. In the ipsilesional SC, a transient decrease in NAA:Cr and Glu:Cr was observed relative to the contralateral SC, which was in parallel with a transient increase in Cho:Cr at Day 3 after afferent lesion. A significantly elevated Lac:Cr ratio was observed throughout the 4-week experimental period, which was gradually decreasing along the time course. This decreasing Lac:Cr increase was followed by a later onset of mI:Cr increase at Day 14. Upon application of a self-designed, self-assembly peptide nanofiber scaffold known to provide immediate hemostasis and permit axonal growth through the site of treated lesion, no transient changes as observed in the untreated groups were found in the treated ipsilesional SC. It is concluded that 1H MRS may help monitor metabolic changes in the superior colliculi upon retinotectal deafferentation, and is a potential tool for the study of functional effect of CNS lesions in vivo