抄録
Purpose: Previously, we demonstrated that transcorneal electrical stimulation(TcES) promotes the survival of axotomized retinal ganglion cells (RGCs) in adult rats. But the mechanism underlying TcES-induced neuroprotective effect was unclear. Electrical stimulation is known to upregulate TrkB and BDNF mRNA in various neurons. We therefore investigated what kind of mRNAs of neurotrophic factors or their receptors were upregulated in the retina after TcES.Materials and Methods: Adult male Wistar rats were used in this study. TcES (100 µA, 20Hz, 1 hour) was applied to the left eye without optic nerve transection. Rats were divided into subgroups according to the terms of survival ranged from 1 hour to 7 days after TcES. The retinas were desected from the enucleated eyes and total RNA was obtained from the retina. RT-PCR analysis was performed to determine the mRNA expressions of the following neurotrophic factors and receptors: BDNF and TrkB ; CNTF and CNTF-receptor ; bFGF and FGF receptor-1 ; IGF-1 and IGF-1 receptor. Results: RT-PCR analysis showed that the expression of IGF-1 mRNA increased at 1 day after TcES and remained elevated over 7 days after TcES. However, mRNAs of other neurotrophic factors and receptors did not change.Conclusion: IGF-1 mRNA was upregulated in the retina after TcES. This result suggests that IGF-1 may play a role in the TcES-induced neuroprotection on axotomized RGCs in vivo. [Jpn J Physiol 54 Suppl:S163 (2004)]
