Portal de Periódicos da CAPES

Mediation of Neuronal Apoptosis by Enhancement of Outward Potassium Current

1997; American Association for the Advancement of Science; Volume: 278; Issue: 5335 Linguagem: Inglês

10.1126/science.278.5335.114

1095-9203

Shan Ping Yu, Chen-Hsiung Yeh, Stefano L. Sensi, Byoung Joo Gwag, Lorella M.T. Canzoniero, Z. Shadi Farhangrazi, Howard S. Ying, Min Tian, Laura L. Dugan, Dennis W. Choi,

Cardiac electrophysiology and arrhythmias

Apoptosis of mouse neocortical neurons induced by serum deprivation or by staurosporine was associated with an early enhancement of delayed rectifier ( I K ) current and loss of total intracellular K + . This I K augmentation was not seen in neurons undergoing excitotoxic necrosis or in older neurons resistant to staurosporine-induced apoptosis. Attenuating outward K + current with tetraethylammonium or elevated extracellular K + , but not blockers of Ca 2+ , Cl − , or other K + channels, reduced apoptosis, even if associated increases in intracellular Ca 2+ concentration were prevented. Furthermore, exposure to the K + ionophore valinomycin or the K + -channel opener cromakalim induced apoptosis. Enhanced K + efflux may mediate certain forms of neuronal apoptosis.