Blocking effect of lanthanum on delayed-rectifier K+ current in Drosophila neurons.
The delayed-rectifier potassium current (IKDR) is important in regulating neuronal excitability. The authors characterized the neurotoxic effect of lanthanum on IKDR. The conventional whole-cell patch-clamp technique was applied to cultured Drosophila neurons derived from embryonic neuroblasts. IKDR was measured from neurons before and after application of 0.1 mM lanthanum to the external saline. IKDR was smaller in the lanthanum-containing saline (441 +/- 57 pA) than in the control saline (680 +/- 35 pA) (p <.001). Activation and inactivation of IKDR were unchanged by lanthanum. Because these results suggest that lanthanum acts as a potent blocker of IKDR, neuronal excitability may be altered during lanthanum neurotoxicity.
Alshuaib
Waleed B
WB
Department of Physiology, Faculty of Medicine, Kuwait University, Safat, Kuwait. waleed@hsc.kuniv.edu.kw
Mathew
Mini V
MV
D000818:Animals; D002121:Calcium Channel Blockers / Q000494:pharmacology; D002478:Cells, Cultured; D004330:Drosophila; D004625:Embryo, Nonmammalian; D015640:Ion Channel Gating / Q000187:drug effects; D007811:Lanthanum / Q000494:pharmacology*; D008564:Membrane Potentials / Q000187:drug effects; D009474:Neurons / Q000187:drug effects* / Q000378:metabolism; D018408:Patch-Clamp Techniques / Q000379:methods; D026902:Potassium Channel Blockers / Q000494:pharmacology*; D024661:Potassium Channels, Inwardly Rectifying / Q000037:antagonists & inhibitors*; D019789:Tetraethylammonium / Q000494:pharmacology
D002121:Calcium Channel Blockers; D026902:Potassium Channel Blockers; D024661:Potassium Channels, Inwardly Rectifying; D019789:Tetraethylammonium; D007811:Lanthanum