ユニークな麻酔理論を提唱した麻酔科医：上田一作 2．上田研究室からの麻酔メカニズム理論とその論争

Professor Issaku Ueda：Anesthesiologist who Proposed Unique Mechanisms of Anesthetic Actions. 2．Theory of Anesthetic Mechanism from Ueda’s Lab. and Controversies with Other Researchers

要旨

　ユタ大学麻酔科教授の上田一作は，物理化学的な手法による独自のメカニズム理論を国際的に発信した。麻酔薬は脂質膜やタンパク質ではなく，それら生体分子の構造構成に必要とされる水分子に作用する界面電縮水解放説を提唱した。また，麻酔の圧拮抗現象を以前の臨界体積仮説に対して熱力学に基づく剰余体積仮説により説明し，さらに，リン脂質膜への麻酔薬の分配係数によるアルコールのカットオフ現象を熱力学的な解釈により示した。最後にタンパク受容体説を支持するホタル発光酵素ルシフェラーゼへの麻酔作用について，ほかの研究者との論争を紹介する。

　Issaku Ueda’s original theories of anesthesia mechanisms based on physicochemical methods are known internationally. Dr. Ueda was a professor in the Department of Anesthesiology at University of Utah（Salt Lake City, UT, USA）. He proposed the new theory of interfacial electrostricted water release which posits that anesthetics act not on lipid membranes or proteins, but rather on the water molecules required for the structural organization of those biomolecules. He also explained the pressure reversal of anesthesia by the mean excess volume hypothesis based on thermodynamics against the critical volume hypothesis. Dr. Ueda further thermodynamically interpreted the cut-off phenomenon of alcohol due to the partition coefficients of anesthetics into phospholipid membranes. This report discusses the work of Dr. Ueda and introduces some controversies with other researchers regarding the anesthetic action on the firefly luciferase that supports the protein receptor theory.