Inhibition of N-methyl-D-aspartate receptors by straight-chain diols: Implications for the mechanism of the alcohol cutoff effect

Peoples, RW; Ren, H

HERO ID

4674221

Reference Type

Journal Article

Year

2002

Language

English

PMID

11752218

HERO ID 4674221
In Press No
Year 2002
Title Inhibition of N-methyl-D-aspartate receptors by straight-chain diols: Implications for the mechanism of the alcohol cutoff effect
Authors Peoples, RW; Ren, H
Journal Molecular Pharmacology
Volume 61
Issue 1
Page Numbers 169-176
Abstract n-Alkanol inhibition of N-methyl-D-aspartate (NMDA) receptors exhibits a "cutoff" effect: alcohols with up to eight to nine carbon atoms inhibit the receptor, whereas larger alcohols do not. This phenomenon was originally proposed to result from size exclusion; i.e., alcohols above the cutoff are too large to bind to an amphiphilic site on the receptor. In the present study, 1,Omega-diols with 3 to 14 carbon atoms inhibited NMDA-activated current in Chinese hamster ovary and human embryonic kidney 293 cells transiently expressing NR1 and NR2B NMDA receptor subunits. Results of fluctuation analysis experiments were consistent with a similar mechanism of inhibition of NMDA-activated current by alcohols and diols. The average change in apparent energy of binding of the diols caused by addition of a methylene group was 2.1 kJ/mol, which is consistent with an important role of hydrophobic interactions. Because 1,Omega-diols with 9 to 14 carbons inhibited NMDA-activated current, despite having molecular volumes exceeding that at the cutoff point for 1-alkanols, a size exclusion mechanism seems inadequate to explain the cutoff effect. A disparity in hydrophobicity values at the cutoff for alcohols and diols, however, revealed that hydrophobicity could also not entirely explain the cutoff phenomenon. From these results, it seems that the cutoff effect on NMDA receptors results primarily from the inability of long-chain alcohols to achieve adequate concentrations at their site of action due to low aqueous solubility, although other factors may also contribute to the effect.
Doi 10.1124/mol.61.1.169
Pmid 11752218
Wosid WOS:000173135000020
Is Certified Translation No
Dupe Override No
Is Public Yes
Language Text English