Altered outward K(+) currents in Drosophila larval neurons of memory mutants rutabaga and amnesiac.
K(+) currents in cultured Drosophila larval neurons have been classified into four categories according to their inactivation time constants, relative amplitude, and response to K(+) channel blockers 4-AP and tetraethylammonium. The percentage (65%) of neurons displaying K(+) currents which were reduced to 30% in amplitude by 5 mM cyclic adenosine monophosphate (cAMP) analog 8-bromo-cAMP in both Drosophila memory mutants rutabaga (rut) and amnesiac (amn) was significantly larger than that (50%) in wild type. This initial characterization provides evidence for altered K(+) currents in both rut and amn mutants. Arachidonic acid, a specifical inhibitor of Kv4 family (shal) K(+) channels, was found to inhibit K(+) currents in cultured Drosophila neurons, suggesting the presence of shal channels in these neurons.
Yu
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D
Laboratory of Visual Information Processing, Department of Neurobiology, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, People's Republic of China.
Feng
C
C
Guo
A
A
D015761:4-Aminopyridine / Q000494:pharmacology; D015124:8-Bromo Cyclic Adenosine Monophosphate / Q000494:pharmacology; D000262:Adenylyl Cyclases / Q000172:deficiency* / Q000235:genetics / Q000502:physiology; D000818:Animals; D016718:Arachidonic Acid / Q000494:pharmacology; D001921:Brain / Q000166:cytology / Q000254:growth & development; D002478:Cells, Cultured; D029721:Drosophila Proteins; D004331:Drosophila melanogaster / Q000235:genetics* / Q000254:growth & development / Q000502:physiology; D017952:Ganglia, Invertebrate / Q000166:cytology / Q000254:growth & development; D019476:Insect Proteins / Q000235:genetics* / Q000502:physiology; D015640:Ion Channel Gating / Q000187:drug effects; D017136:Ion Transport / Q000187:drug effects; D007814:Larva; D008568:Memory / Q000502:physiology*; D009474:Neurons / Q000378:metabolism*; D009479:Neuropeptides / Q000172:deficiency* / Q000235:genetics / Q000502:physiology; D018408:Patch-Clamp Techniques; D011188:Potassium / Q000378:metabolism*; D026902:Potassium Channel Blockers; D015221:Potassium Channels / Q000378:metabolism* / Q000502:physiology; D024642:Potassium Channels, Voltage-Gated; D051672:Shal Potassium Channels; D019789:Tetraethylammonium / Q000494:pharmacology
D029721:Drosophila Proteins; D019476:Insect Proteins; D009479:Neuropeptides; D026902:Potassium Channel Blockers; D015221:Potassium Channels; D024642:Potassium Channels, Voltage-Gated; D051672:Shal Potassium Channels; C497024:Shal protein, Drosophila; C093565:amn protein, Drosophila; D015124:8-Bromo Cyclic Adenosine Monophosphate; D016718:Arachidonic Acid; D019789:Tetraethylammonium; D015761:4-Aminopyridine; D000262:Adenylyl Cyclases; D011188:Potassium