Activation of K+ channels by stimulation of metabotropic glutamate receptors.
Single channel potassium currents activated indirectly via stimulation of metabotropic receptors were recorded in cell-attached patches on hippocampal neurones in slices from neonatal rats. When metabotropic receptors in the area outside of the patch are stimulated by glutamate, quisqualate and trans-ACPD, single channel currents appear with a predominant conductance level of about 20 pS. From the reversal potential and substitution of ionic species, we established that the currents are carried by potassium ions. Using selective blockers of ionotropic receptors in conjunction with specific agonists for the metabotropic receptor, it was ascertained that the channel observed is linked to metabotropic receptors. The currents display submaximal conductance states and fluctuate rapidly between evenly-spaced conductance sublevels.
Premkumar
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Department of Chemistry, Australian National University, Canberra.
Chung
S H
SH
D018750:6-Cyano-7-nitroquinoxaline-2,3-dione / Q000494:pharmacology; D000818:Animals; D003515:Cycloleucine / Q000031:analogs & derivatives / Q000494:pharmacology; D018698:Glutamic Acid / Q000494:pharmacology; D006624:Hippocampus / Q000187:drug effects*; D066298:In Vitro Techniques; D009474:Neurons / Q000187:drug effects*; D015221:Potassium Channels / Q000187:drug effects*; D016318:Quisqualic Acid / Q000494:pharmacology; D051381:Rats; D017208:Rats, Wistar; D018094:Receptors, Metabotropic Glutamate / Q000187:drug effects*; D013268:Stimulation, Chemical; D014633:Valine / Q000031:analogs & derivatives / Q000494:pharmacology
D015221:Potassium Channels; D018094:Receptors, Metabotropic Glutamate; D003515:Cycloleucine; C036361:1-amino-1,3-dicarboxycyclopentane; D018698:Glutamic Acid; D018750:6-Cyano-7-nitroquinoxaline-2,3-dione; C056639:2-amino-5-phosphopentanoic acid; D016318:Quisqualic Acid; D014633:Valine