shATGL treatment of INS832/13 cells reduces the expression of ATGL mRNA and protein and decreases TG lipase activity. INS832/13 cells were electroporated in the presence of empty vector (Mock), scrATGL (Scr), or shATGL. Nontransfected cells served as additional control. A, time course of the effect of shATGL on ATGL mRNA expression in INS832/13 cells cultured in complete RPMI medium at 11.1 mm glucose. B, ATGL protein expression was determined by Western blot analysis using actin as a control. C, triglyceride lipase activity of cytosolic extracts of INS832/13 cells using radiolabeled triolein as a substrate. Means ± S.E. are of three experiments performed in duplicate. *, p < 0.05; **, p < 0.01; ***, p < 0.001 versus time 13 h after transfection (A) or versus scrambled ATGL (B and C), by unpaired two-tailed Student's t test.