Non-dioxin-like polychlorinated biphenyl 19 has distinct effects on human Kv1.3 and Kv1.5 channels.

Non-dioxin-like polychlorinated biphenyl 19 has distinct effects on human Kv1.3 and Kv1.5 channels. Toxicol Appl Pharmacol. 2020 Dec 11;:115365 Authors: Kim JH, Hwang S, Jo SH Abstract Polychlorinated biphenyls (PCBs) are persistent and serious organic pollutants and can theoretically form 209 congeners. PCBs can be divided into two categories: dioxin-like (DL) and non-DL (NDL). NDL-PCBs, which lack aryl hydrocarbon receptor affinity, have been shown to perturb the functions of Jurkat T cells, cerebellar granule cells, and uterine cells. Kv1.3 and Kv1.5 channels are important in immune and heart functions, respectively. We investigated the acute effects of 2,2',6-trichlorinated biphenyl (PCB19), an NDL-PCB, on the currents of human Kv1.3 and Kv1.5 channels. PCB19 acutely blocked the Kv1.3 peak currents concentration-dependently with an IC50 of ~2 μM, without changing the steady-state current. The PCB19-induced inhibition of the Kv1.3 peak current occurred rapidly and voltage-independently, and the effect was irreversible, excluding the possibility of genomic regulation. PCB19 increased the time constants of both activation and inactivation of Kv1.3 channels, resulting in the slowing down of both ultra-rapid activation and intrinsic inactivation. However, PCB19 failed to alter the steady-state curves of activation and inactivation. Regarding the Kv1.5 channel, PCB19 affected neither the peak current nor the steady-state current at ...
Source: Toxicology and Applied Pharmacology - Category: Toxicology Authors: Tags: Toxicol Appl Pharmacol Source Type: research