title: Chemically activated channels in muscle and spinal cord.
abstract: The patch clamp can be used to record single chemically activated channel currents in a variety of cell culture preparations. In the case of the gamma-aminobutyric acid (GABA) response in spinal cord cell culture, the channel is Cl - selective. Cl- can be made to flow into or out of a cell by changing the direction of the electrochemical driving force for Cl-; as a result, positive or negative channel currents are produced. Channel currents generated by GABA and the GABA agonists muscimol and pentobarbital have the same amplitude. The kinetics of channel gating are studied by analyzing distributions of dwell times in conducting and nonconducting states. Such analyses of the GABA-activated channel and the acetylcholine-activated channel reveal that gating is complex. More elaborate procedures of data analysis have been used in an attempt to elucidate detailed molecular gating mechanisms.
mesh_terms: D000109:Acetylcholine / Q000494:pharmacology; D000818:Animals; D002712:Chlorides / Q000378:metabolism; D007473:Ion Channels / Q000187:drug effects*; D007700:Kinetics; D008564:Membrane Potentials / Q000187:drug effects; D009118:Muscimol / Q000494:pharmacology; D009469:Neuromuscular Junction / Q000187:drug effects*; D010424:Pentobarbital / Q000494:pharmacology; D011950:Receptors, Cholinergic / Q000187:drug effects; D011963:Receptors, GABA-A / Q000187:drug effects; D013116:Spinal Cord / Q000187:drug effects*; D013268:Stimulation, Chemical; D009435:Synaptic Transmission / Q000187:drug effects*; D005680:gamma-Aminobutyric Acid / Q000494:pharmacology
chemical_list: D002712:Chlorides; D007473:Ion Channels; D011950:Receptors, Cholinergic; D011963:Receptors, GABA-A; D009118:Muscimol; D005680:gamma-Aminobutyric Acid; D010424:Pentobarbital; D000109:Acetylcholine