Elevation of intracellular calcium reduces voltage-dependent potassium conductance in human T cells.
Both voltage-activated potassium channels and the concentration of free intracellular calcium have been implicated in the activation of T lymphocytes. Using the patch-clamp technique, we now show an unexpected relationship between the level of intracellular calcium [Ca]i in human lymphocytes and the amplitude of a voltage-dependent current: the elevation of [Ca]i decreases the potassium conductance. This is in contrast to other systems where [Ca]i activates K+ channels. Our results suggest that the level of intracellular calcium regulates the effective number of K+ channels capable of being activated.
P
P
Bregestovski
A
A
Redkozubov
A
A
Alexeev
D000255:Adenosine Triphosphate / Q000494:pharmacology; D000001:Calcimycin / Q000494:pharmacology; D002118:Calcium / Q000378:metabolism*; D004553:Electric Conductivity; D006801:Humans; D007473:Ion Channels / Q000378:metabolism; D008564:Membrane Potentials; D011188:Potassium / Q000378:metabolism*; D013601:T-Lymphocytes / Q000502:physiology*
D007473:Ion Channels; D000001:Calcimycin; D000255:Adenosine Triphosphate; D011188:Potassium; D002118:Calcium