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PubMed · 2159183

Anesthesia cutoff phenomenon: interfacial hydrogen bonding.

J S Chiou·S M Ma·H Kamaya·I Ueda
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Abstract

Anesthesia "cutoff" refers to the phenomenon of loss of anesthetic potency in a homologous series of alkanes and their derivatives when their sizes become too large. In this study, hydrogen bonding of 1-alkanol series (ethanol to eicosanol) to dipalmitoyl-L-alpha-phosphatidylcholine (DPPC) was studied by Fourier transform infrared spectroscopy (FTIR) in DPPC-D2O-in-CCl4 reversed micelles. The alkanols formed hydrogen bonds with the phosphate moiety of DPPC and released the DPPC-bound deuterated water, evidenced by increases in the bound O-H stretching signal of the alkanol-DPPC complex and also in the free O-D stretching band of unbound D2O. These effects increased according to the elongation of the carbon chain of 1-alkanols from ethanol (C2) to 1-decanol (C10), but suddenly almost disappeared at 1-tetradecanol (C14). Anesthetic potencies of these alkanols, estimated by the activity of brine shrimps, were linearly related to hydrogen bond-breaking activities below C10 and agreed with the FTIR data in the cutoff at C10.

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1,2-DipalmitoylphosphatidylcholineAlcoholsAnesthesiaCarbon TetrachlorideDeuteriumDeuterium OxideFourier AnalysisHydrogen BondingLiposomesModels, BiologicalStructure-Activity RelationshipThermodynamicsWaterJournal ArticleResearch Support, U.S. Gov't, Non-P.H.S.Research Support, U.S. Gov't, P.H.S.

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J S Chiou, S M Ma, H Kamaya, I Ueda. 1990-05-04. Anesthesia cutoff phenomenon: interfacial hydrogen bonding.. https://doi.org/10.1126/science.2159183

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