Are sulfhydryl groups essential for function of the glutamate-operated receptor-ionophore complex?
We monitored glutamate- or kainic acid-induced inward currents in pyramidal neurons of the rat hippocampus to determine a possible chemical modification of sulfhydryl residues on glutamate-receptor-ionophore complexes. Organic and inorganic mercury compounds such as HgCl2 and n-chloromercuribenzoate, 5,5'-dithiobis (2-nitrobenzoic acid) and N-ethylmaleimide depressed glutamate- or kainate-induced responses while the mercury compounds inhibited the kainate response, in a non-competitive manner. The responses inhibited by these agents were dose-dependently recovered by adding cysteine or glutathione. These observations suggest that the excitatory glutamate-receptor-ionophore complex includes sulfhydryl residues, components which may play a role in related functions.
D000818:Animals; D003545:Cysteine / Q000494:pharmacology; D006624:Hippocampus / Q000502:physiology*; D007473:Ion Channels / Q000187:drug effects* / Q000378:metabolism; D007476:Ionophores / Q000378:metabolism*; D007608:Kainic Acid / Q000494:pharmacology; D008564:Membrane Potentials / Q000187:drug effects; D008627:Mercuric Chloride / Q000494:pharmacology; D009474:Neurons / Q000502:physiology; D051381:Rats; D017470:Receptors, Glutamate; D017981:Receptors, Neurotransmitter / Q000378:metabolism*; D013438:Sulfhydryl Compounds / Q000378:metabolism* / Q000502:physiology
D007473:Ion Channels; D007476:Ionophores; D017470:Receptors, Glutamate; D017981:Receptors, Neurotransmitter; D013438:Sulfhydryl Compounds; D008627:Mercuric Chloride; D003545:Cysteine; D007608:Kainic Acid