探討海馬迴內NMDAR與CaMKII經超音波刺激後磷酸化的反應

Abstract

在過去幾年，有開發許多非侵入式穿顱刺激的裝置。研究指出穿顱磁刺激會造成神經表面古安酸受體的突觸，加速神經的傳遞。透過服用鈣離子與NMDAR相關藥物可以抑制穿顱磁刺激的結果。相關的人體實驗，在日本東北大學，對患有阿茲海默症的病人進行頭部刺激，與未刺激組進行比較，發現經過刺激的病人皆有好轉的情況。可見非侵入式經顱刺激是可以對退化神經的連結，達到一定的影響。 因為於人體實驗中發現超音波對於神經退化的疾病，可以達到其治療作用，所以希望對於其內部的蛋白質運作機制有所探討，先前的研究認為ASIC1為接收超音波受器其一，但因為還可以看到其超音波刺激對於少部分ERK的磷酸化反應，推測還有其他接受超音波受體的蛋白，於是透過液相-層析質譜儀在分子調控中心發現NMDAR 與CaMKII，透過文獻相關回顧可以發現NMDAR 與CaMKII的活化與學習、情緒、記憶相關，在大腦內的功能運作佔很重要的一部分。 研究目的為觀察超音波刺激對於海馬迴內NMDAR與CaMKII磷酸化的反應，本次實驗使用實驗室開發的超音波刺激裝置，水為傳遞的介質，減少擔心升溫的問題也透過優化裂解液去偵測磷酸化蛋白反應。 在本次實驗中可以觀察到超音波刺激確實造成NMDAR與CaMKII的磷酸化反應，只是不同位點被活化的刺激能量參數不同，CaMKII T286對於刺激時間較於敏感，CaMKII Y231則是對於低能量的刺激較敏感，NMDAR S1303的磷酸化則是需要在較高電壓下刺激才能觀察到反應，而NMDAR磷酸化對神經傳遞的方式與速度有一定的影響。至於NMDAR與CaMKII磷酸化對大腦所造成後續的機制作用與傳遞的速度，還是要透過相關實驗去驗證。

In the past few years, there have been many devices developed for non-invasive transcranial stimulation. Studies have pointed out that transcranial magnetic stimulation can cause synapses of glutamate receptors on the nerve surface and accelerate neurotransmission. The results of transcranial magnetic stimulation can be inhibited by taking calcium ions and NMDAR-related drugs. At Tohoku University in Japan, the human experiment, patients with Alzheimer's disease were stimulated, and compared with the unstimulated patients. It was found that the stimulated patients all improved. From this, it can be seen that non-invasive transcranial stimulation have a certain connection of degenerative nerves. It was found that in human experiments, ultrasound can achieve its therapeutic effect on neurodegenerative diseases. Therefore, we explore operation mechanism of internal protein. Previous studies believed that ASIC1 is one of the receptors of ultrasound. However, it can be seen that the small part phosphorylation of ERK is stimulated by ultrasound, so our team speculated that there are other proteins relate to ultrasound. Through the ultrasound stimulation, NMDAR and CaMKII were found in the molecular regulation center through liquid chromatography-mass spectrometry. Most of literature review found that the activation of NMDAR and CaMKII is related to learning, emotion, and memory, and the important functional operation in the brain. The purpose of the study is observing the phosphorylation response of ultrasonic stimulation of NMDAR and CaMKII in the hippocampus. In this experiment, it can be observed that ultrasonic stimulation causes the phosphorylation of NMDAR and CaMKII. CaMKII T286 is more sensitive to stimulation time, while CaMKII Y231 has suitable stimulation parameter. As for the phosphorylation of NMDAR S1303 be stimulated at a higher voltage to activated it, and the phosphorylation of NMDAR has a certain influence on the mode and speed of neurotransmission. As for the subsequent mechanism and transmission speed of NMDAR and CaMKII phosphorylation on the hippocampus, it still needs to be verified through relevant experiments.