Yoshida Hirohide, Kobayashi Daisaku, Ohkubo Satoko, Nakahata Norimichi
Department of Cellular Signaling, Tohoku University, Aoba 6-3, Aramaki, Aoba-ku, Sendai 980-8578, Japan.
Eur J Pharmacol. 2006 Jul 1;540(1-3):1-9. doi: 10.1016/j.ejphar.2006.04.008. Epub 2006 May 22.
We evaluated the role of ATP in functions of human HaCaT keratinocytes. ATP was released from HaCaT cells by changing the culture medium. Reverse transcription-polymerase chain reaction analysis revealed that HaCaT cells expressed multiple P2 purinergic receptor mRNAs. UTP was the most potent agonist to increase the intracellular Ca2+ concentration ([Ca2+]i). UTP and ATP caused the accumulation of [3H]inositol phosphates, suggesting that UTP binds to the Gq/11-coupled P2Y receptor. UTP increased IL-6 mRNA and protein levels, and the increases were inhibited by a P2 purinergic receptor antagonist (suramin, 300 microM). While a protein kinase C inhibitor (GF109203X, 10 microM) was without effect, an intracellular free Ca2+ chelator (BAPTA-AM, 50 microM) suppressed UTP-mediated IL-6 induction. These results suggest that 1) ATP is released from HaCaT cells upon physical stimulation and may act as an autocrine molecule, and 2) the stimulation of P2Y receptors causes IL-6 production via mRNA expression through [Ca2+]i elevation.
我们评估了ATP在人HaCaT角质形成细胞功能中的作用。通过更换培养基从HaCaT细胞中释放出ATP。逆转录-聚合酶链反应分析显示，HaCaT细胞表达多种P2嘌呤能受体mRNA。UTP是增加细胞内Ca2+浓度（[Ca2+]i）的最有效激动剂。UTP和ATP导致[3H]肌醇磷酸的积累，表明UTP与Gq/11偶联的P2Y受体结合。UTP增加了IL-6 mRNA和蛋白水平，并且这些增加被P2嘌呤能受体拮抗剂（苏拉明，300 microM）抑制。虽然蛋白激酶C抑制剂（GF109203X，10 microM）没有作用，但细胞内游离Ca2+螯合剂（BAPTA-AM，50 microM）抑制了UTP介导的IL-6诱导。这些结果表明：1）物理刺激后ATP从HaCaT细胞中释放，可能作为自分泌分子起作用；2）P2Y受体的刺激通过[Ca2+]i升高导致IL-6通过mRNA表达产生。
