Page 36 - F. Cell biology

[F. Cell biology-22]

PCB77 changes the steady-state current and kinetics of the

Kv1.3 channel

Jong-hui Kim¹˙²˙*, Su-Hyun Jo¹˙²

¹Interdisciplinary Graduate Program for BIT Medical Convergence, Kangwon National University, Chuncheon 200-

701, Korea , ²Department of Physiology, School of Medicine, Kangwon National University, Chuncheon 200-701,
Korea

Polychlorinated biphenyls (PCBs) are a family of bicyclic chlorinated aromatic hydrocarbons. PCBs unique chemical

properties and the low cost of producing PCBs have contributed to their extensive industrial use. Acute and long-

term exposure to the compounds has been known to causes diseases such as developmental delays and motor
dysfunction. The presence of PCBs in the environment presents various toxic effects in vivo and in vitro, but the
mechanism is not yet fully understood. One immune-modulating mechanism is achieved by the Kv1.3 voltage-

dependent potassium channel, which is expressed highly in lymphocytes including effector memory T lymphocytes.
Here we studied the effect Polychlorinated biphenyls (3,3′,4,4′-tetrachlorobiphenyl, PCB77) on human Kv1.3 channels

expressed in Xenopus oocytes. When we exposed the oocytes with PCB77 for 8 min and 15min, the steady state
current of Kv 1.3 channel increased significantly. In addition, the τ values of the Kv1.3 current trace was increased

50% by 10 nM PCB77. These results suggest that PCBs could affect the heart in a way that did not block, a voltage-
dependent potassium channel, Kv1.3 channel directly.These results suggest that PCB77 shows physiological toxicity

by increases the current of the Kv1.3 channel.