Fischer L J, Zhou H R, Wagner M A
Institute for Environmental Toxicology, Michigan State University, East Lansing 48824, USA.
Life Sci. 1996;59(24):2041-9. doi: 10.1016/s0024-3205(96)00557-7.
Polychlorinated biphenyls (PCBs) possess a variety of biological effects, including alterations in growth, development and metabolism, that may be dependent on insulin. However, no reports on the action of PCBs on cells which produce and secrete insulin are available. The current study examined the ability of a commercial mixture of PCBs (Aroclor 1254) and three specific PCB congeners, to alter the release of insulin using the hormone producing cell line RINm5F. Exposure of cells to Aroclor 1254 (A-1254) produced a concentration-dependent increase in media insulin reaching a peak, when expressed as percent of control, at 30 min. In spite of continued exposure, media insulin relative to control declined and no treatment-related difference was observed at 48 hrs. Cellular levels of the hormone declined as much as 50% by that time. The insulin releasing action of A-1254 was mimicked by each of the non-coplanar congeners 2,2',4,4'-tetrachlorobiphenyl (TCB) and 2,2',4,4',5,5'-hexachlorobiphenyl (HCB) but the coplanar congener 3,3',4,4'-TCB showed no significant activity. These results indicate that PCBs are capable of producing a release of insulin from RINm5F cells, an effect that is unlikely to be associated with coplanar congeners that initiate their action by binding to the Ah-receptor.
多氯联苯（PCBs）具有多种生物学效应，包括生长、发育和新陈代谢的改变，这些效应可能依赖于胰岛素。然而，目前尚无关于PCBs对产生和分泌胰岛素的细胞作用的报道。本研究使用产生激素的细胞系RINm5F，检测了一种商业PCBs混合物（Aroclor 1254）和三种特定的PCBs同系物改变胰岛素释放的能力。将细胞暴露于Aroclor 1254（A - 1254）后，培养基中胰岛素浓度呈浓度依赖性增加，30分钟时达到峰值（以对照百分比表示）。尽管持续暴露，但相对于对照，培养基中胰岛素在48小时时下降，且未观察到与处理相关的差异。此时细胞内激素水平下降多达50%。非共面同系物2,2',4,4'-四氯联苯（TCB）和2,2',4,4',5,5'-六氯联苯（HCB）均可模拟A - 1254的胰岛素释放作用，但共面同系物3,3',4,4'-TCB未显示出显著活性。这些结果表明，PCBs能够促使RINm5F细胞释放胰岛素，这种效应不太可能与通过结合芳烃受体启动作用的共面同系物有关。
