Journal: The Journal of General Physiology

Article Title: Delimiting the Binding Site for Quaternary Ammonium Lidocaine Derivatives in the Acetylcholine Receptor Channel

doi:

Figure Lengend Snippet: Aligned sequences of the M2 segments of mouse-muscle ACh receptor subunits. The numbering is that of the α subunit. The predicted membrane-spanning segments correspond to αM243 to αV261. The intracellular ( IN ) and extracellular ( EX ) ends are indicated. *Residues are aligned with residues in the ACh receptor from Torpedo electric tissue that were labeled by noncompetitive inhibitor derivatives. Mutations of the boxed-in residues affected channel block by QX-222. Cysteines substituted for the residues in bold italics are exposed in the channel in the presence of ACh (tested only in α and β). See text for references.

Article Snippet: The quaternary lidocaine derivative 2-(triethylammonio)- N -(2,6-dimethylphenyl)acetamide bromide (QX-314) was from Alomone Laboratories (Jerusalem, Israel) and from Astra (Westborough, MA), and 2-(trimethylammonio)- N -(2,6-dimethylphenyl)acetamide chloride (QX-222) was from Astra.

Techniques: Labeling, Blocking Assay

Journal: The Journal of General Physiology

Article Title: Delimiting the Binding Site for Quaternary Ammonium Lidocaine Derivatives in the Acetylcholine Receptor Channel

doi:

Figure Lengend Snippet: Structures of QX-314 and QX-222.

Article Snippet: The quaternary lidocaine derivative 2-(triethylammonio)- N -(2,6-dimethylphenyl)acetamide bromide (QX-314) was from Alomone Laboratories (Jerusalem, Israel) and from Astra (Westborough, MA), and 2-(trimethylammonio)- N -(2,6-dimethylphenyl)acetamide chloride (QX-222) was from Astra.

Techniques:

Journal: The Journal of General Physiology

Article Title: Delimiting the Binding Site for Quaternary Ammonium Lidocaine Derivatives in the Acetylcholine Receptor Channel

doi:

Figure Lengend Snippet: The protection by QX-314 and QX-222 of Cys-substituted residues in M2 against reaction with MTSEA. For each mutant, the rate constant of the reaction in the presence of channel blocker and ACh ( k blocked ) and the rate constant of the reaction in the presence of ACh alone ( k open ) were determined as described in methods . The extent of protection is taken as 1 − ( k blocked / k open ). The means of two to four determinations and average errors or SEM are plotted. The lighter bars represent the protection by QX-314, and the darker bars represent the protection by QX-222. *ND.

Article Snippet: The quaternary lidocaine derivative 2-(triethylammonio)- N -(2,6-dimethylphenyl)acetamide bromide (QX-314) was from Alomone Laboratories (Jerusalem, Israel) and from Astra (Westborough, MA), and 2-(trimethylammonio)- N -(2,6-dimethylphenyl)acetamide chloride (QX-222) was from Astra.

Techniques: Mutagenesis