Fig. 5
Derivatives of FMP-API-1 robustly activate AQP2. a Derivatives of FMP-API-1. The chemical formulas of FMP-API-1, FMP-API-1/27, and FMP-API-1/28 are shown. b Dose-response studies of FMP-API-1/27. FMP-API-1/27 (25–250 µM) was added to the basolateral side of the mpkCCD cells for 1 h. Representative blots of three independent experiments are shown. c Western blot analysis of AQP2 in mouse kidneys. The C57BL/6 mice were intraperitoneally infused with DMSO, FMP-API-1/27 (30 mg/kg), or dDAVP (100 μg/kg). Samples were collected 1 h after intraperitoneal infusion. Representative blots of four independent experiments are shown. d AQP2 phosphorylation by FMP-API-1/27 in the NDI mouse model. C57BL/6 mice were subcutaneously infused with DMSO or tolvaptan (25 mg/kg/day) for 24 h using osmotic minipumps, and then intraperitoneally infused with DMSO or FMP-API-1/27 (30 mg/kg). Samples were collected 1 h after the intraperitoneal infusion. Representative blots of four independent experiments are shown. e Increase in urine concentrating ability by FMP-API-1/27 in the NDI mouse model. (Upper) The time course of the experiment is shown. After measurement of basal urine osmolality in metabolic cages for 24 h, C57BL/6 mice were subcutaneously infused with tolvaptan (25 mg/kg/day) for 24 h using osmotic minipumps. C57BL/6 mice were then intraperitoneally infused with FMP-API-1/27 (30 mg/kg). Urine samples were collected at the indicated times. (Middle) Representative urine samples of three independent experiments are shown. (Lower) The time course of urine osmolality is shown. f Drug effects of FMP-API-1/27 via the different routes of administration. The C57BL/6 mice were treated with intraperitoneal (ip; 30 mg/kg) or subcutaneous (sc; 80 mg/kg) injection of FMP-API-1/27. Samples were collected at the indicated times. Representative blots of four independent experiments are shown. g The effects of FMP-API-1/27 on PKA activity. The C57BL/6 mice were intraperitoneally infused with DMSO or FMP-API-1/27 (30 mg/kg). Samples were collected 1 h after intraperitoneal infusion. Representative blots of three independent experiments are shown
