Modification of K+ channel properties induced by fatty acids in neuroblastoma cells.
The effects of fatty acids on voltage-dependent potassium (K+) channels in neuroblastoma cells were studied using the whole-cell current recording technique. At a concentration of 5 microM, unsaturated and medium chain length (C10-C14) saturated fatty acids accelerated the apparent inactivation of the K+ current. This effect was reversed by albumin. In the absence of exogenous fatty acids, albumin slowed the inactivation of the K+ current. The acceleration of the K+ current inactivation induced by unsaturated fatty acids was associated with an increase in the sensitivity of K+ channels to 4-amino-pyridine. It is concluded that kinetic and pharmacological properties of K+ channels are, in part, controlled by membrane fatty acids which, in this way, should contribute to an apparent diversity of K+ channels and the modulation of cell excitability.
Rouzaire-Dubois
B
B
Laboratoire de Physiologie Comparée, URA CNRS 1121, Orsay, France.
Gérard
V
V
Dubois
J M
JM
D000418:Albumins / Q000502:physiology; D000818:Animals; D004553:Electric Conductivity; D005227:Fatty Acids / Q000502:physiology*; D007700:Kinetics; D009447:Neuroblastoma; D019301:Oleic Acid; D009829:Oleic Acids / Q000502:physiology; D015221:Potassium Channels / Q000378:metabolism*; D014407:Tumor Cells, Cultured
D000418:Albumins; D005227:Fatty Acids; D009829:Oleic Acids; D015221:Potassium Channels; D019301:Oleic Acid