[Blocking of the Ca-dependent inward current in the somatic membrane of mollusk neurons by an elevated intracellular pH].
The action of elevated intracellular pHi (pHi) on the transmembrane ionic currents in the somatic membrane was studied in intracellularly perfused nerve cells from Helix pomatia. Following a change in pHi from 7.3 to 9.0 the amplitude of potassium outward current recorded simultaneously with the calcium inward current was significantly reduced. This was accompanied by a shift of its I-V curve to more positive membrane potential values. In case of the calcium inward current blocking by external Cd2+ ions no reduction of the outward current was observed. Only a shift of its I-V curve along the potential axis remained. The calcium inward current was practically the same. It is suggested that the elevated pHi selectively blocks the Ca-dependent component of the potassium outward current.
D000818:Animals; D002118:Calcium / Q000378:metabolism*; D006372:Helix, Snails / Q000502:physiology; D006863:Hydrogen-Ion Concentration; D066298:In Vitro Techniques; D007473:Ion Channels / Q000502:physiology*; D008564:Membrane Potentials; D009474:Neurons / Q000502:physiology*; D011188:Potassium / Q000378:metabolism
D007473:Ion Channels; D011188:Potassium; D002118:Calcium
Blokirovanie Ca-zavisimogo vykhodiashchego toka v somaticheskoĭ membrane neĭronov molliuskov povyshennym pH vnutrikletochnoĭ sredy.