Interfacial preference of anesthetic action upon the phase transition of phospholipid bilayers and partition equilibrium of inhalation anesthetics between membrane and deuterium oxide

Different distribution of fluorinated anesthetics and nonanesthetics in model membrane: a 19F NMR study

“…Indeed, results from all resonance peaks of F3 and the -CHF2 resonance of isoflurane showed an excellent agreement with the two-site exchange model. The DM/Dw ratios for these two compounds are in line with those found by others for other inhaled anesthetics (e.g., halothane, enflurane, methoxyflurane, and chloroform), confirming that the anesthetics dwell in regions close to the lipid-water interface (Kamaya et al, 1981; Kaneshina et al, 1981; Xu and Tang, 1997;Yokono et al, 1981Yokono et al, , 1989Yoshida et al, 1989). Interestingly, the resonant frequency [PC] (mM) 25 FIGURE 2 Changes in resonant frequencies (Hz at 9.4 T) as a function of PC concentration at 20°C for (a) compound F3 (Fa, 0; Fb, *; Fc, +) and…”

“…The pharmacological difference between anesthetics and nonanesthetics may result from their distinct submolecular distribution in neuronal membranes. It has been shown that some anesthetics (e.g., enflurane, methoxyflurane, halothane, and chloroform) distribute preferentially at the membrane interface (Kamaya et al, 1981;Kaneshina et al, 1981;Yokono et al, 1981Yokono et al, , 1989Yoshida et al, 1989) and that they do not mix isotropically with the lipid core (Kaneshina et al, 1981). It has also been demonstrated for n-alkane anesthetics (Liu et al, 1994b) that the product of MAC X oil/gas partition coefficient X saline/gas partition coefficient is more constant than that of MAC X oil/gas partition coefficient predicted by the Meyer-Overton rule, suggesting that the site of anesthetic action may be neither purely hydrophobic nor purely hydrophilic, but a combination of the two (Liu et al, 1994b).…”

Action mechanism of water soluble ethanol on phospholipid monolayers using a quartz crystal oscillator

“…This result represents that the fluid-rich structure of monolayer shifts to a stabilized state. According to the "non-specific interaction" hypothesis [14,40,41,[57][58][59], the following model of anesthesia mechanism is possible.…”

Physico-Chemical Interactions between Alcohol and Biological Membranes

“…However, the need for detailed studies of the location of ethanol interactions with biological membranes is brought to light even more clearly by the observations made recently with the anesthetic drugs. For example, although inhalation anesthetic agents cause increased motion in the methylene groups within the lipid bilayer as measured by lH magnetic resonance, these effects do not correlate nearly as well with the anesthetic concentrations of these agents as does the disordering effect of these inhalation anesthetics on the phosphorylcholine head groups of phosphatidylcholine measured by the same technique (Shieh et al, 1976;Yokono et al, 1981). These authors have suggested that it is the disruption of electrostatic interactions between phosphorylcholine and adjoining lipids and proteins that leads to the appearance of the anesthetic action.…”