Four Applications of the Anesthetic Cut-off Effect

Abstract

This article presents and analyses several cases in which the use of the cut-off effect is useful. It starts from the fact that an anesthetic effect of homologous agents is always expressible as a function of their chain lengths and that the cut-off point is a point at which the function vanishes. We then investigate four categories of results: (i) whole body effects. (ii) Cases in which the anesthetics affect the Hodgkin-Huxley parameters of a nerve. (iii) Molecular mechanisms of anesthetic action. (iv) The physical chemistry of the anesthetic process. Our discussion shows that it is possible to incorporate these apparently remote results into one framework. It also shows how to compare results that were gathered by independent measuring methods. In some instances we suggest an interpretation, in others we suggest a further gathering of experimental data. One of the deductions indicates that a weakness exists in the lipid theories of anesthesia.

Chemical Boundaries for Detection of Eye Irritation in Humans from Homologous Vapors

“…A direct example is the complexation of 1alkanols with dipalmitoyl-L-α-phosphatidylcholine (DPPC) in D 2 O/CCl 4 reversed micelles (Chiou et al, 1990) that showed a very sharp cut-off at 1-tetradecanol. Examples of cutoffs in the interaction of aqueous homologous series with biological systems include anesthesia (Franks and Lieb, 1985Katz and Aharon, 2000) and effects on enzymes (Fonteh et al, 1989;Franks and Lieb, 1985;McKenzie et al, 1995). The most interesting of the latter is the cut-off effects observed by Franks and Lieb (1985) for the inhibition of activity of the firefly luciferase enzyme by aqueous alkanes and 1-alkanols.…”