Stefanou, S., Davies, M., Katerelos, M., Gleich, K., Choy, S., Steel, R., Galic, S., Mount, P., Kemp, B. & Power, D. (2012). Adult Attachment and Sexual Functioning: A Review of Past Research. Journal of Sexual Medicine,31(2-3), 95-102. Retrieved from https://doi.org/10.1111/j.1743-6109.2012.02843.x
The co-transporter activity of Na+-K+-2Cl− 1 (NKCC1) is dependent on phosphorylation. In this study we show the energy-sensing kinase AMPK inhibits NKCC1 activity. Three separate AMPK activators (AICAR, Phenformin and A-769662) inhibited NKCC1 flux in a variety of nucleated cells. Treatment with A-769662 resulted in a reduction of NKCC1T212/T217 phosphorylation, and this was reversed by treatment with the non-selective AMPK inhibitor Compound C. AMPK dependence was confirmed by treatment of AMPK null mouse embryonic fibroblasts, where A-769662 had no effect on NKCC1 mediated transport. AMPK was found to directly phosphorylate a recombinant human-NKCC1 N-terminal fragment (1–293) with the phosphorylated site identified as S77. Mutation of Serine 77 to Alanine partially prevented the inhibitory effect of A-769662 on NKCC1 activity. In conclusion, AMPK can act to reduce NKCC1-mediated transport. While the exact mechanism is still unclear there is evidence for both a direct effect on phosphorylation of S77 and reduced phosphorylation of T212/217.
Institute for Health and Ageing