FIG. 2.
TCF7L2 knockdown in mouse pancreatic islets and INS-1(832/13) β-cells does not alter glucose-stimulated changes in intracellular free [Ca2+] but alters total cellular ATP and ADP levels. Mouse islets were treated and intracellular adenine nucleotide measured as described in research design and methods (A). Dissociated mouse islet cells (B and C) and INS-1(832/13) β-cells (D and E) were treated with 10 nmol/l fluorescein-labeled siRNA (B and C) or pEGFP-TCF7L2 shRNA (D and E) and incubated with FURA-Red (200 nmol/l; B–E) for [Ca2+]i measurement. Typical traces are shown (C and D). Glucose-induced (3.0 versus 11 mmol/l) [Ca2+]i changes in individual glucose-responsive dissociated mouse islet cells in which TCF7L2 was silenced (B) and the number of INS-1(832/13) cells within the cell population that responded to (20 mmol/l) glucose (E) are shown. Data are means ± SEM, n = 3, unless otherwise stated in the research design and methods. AUC, area under the curve; FITC, fluorescein isothiocyanate.