Autocrine effects of high glucose or palmitate on cAMP production in MIN6c4 cells. MIN6c4 cells were treated with (a) high glucose (25 mmol/l), in the presence or absence of MRS2211 (10 μmol/l), and (b) palmitate (100 μmol/l), in the presence or absence of MRS2211 (10 μmol/l). Cells growing in 6-well plates were treated with the compounds for 30 min, in the presence of 25 μmol/l Rolipram, and were then extracted with 200 μl of 0.1-mol/l hydrochloric acid and analysed for cAMP. Data are given as the means ± SEM (n = 5). *p < 0.05, **p < 0.01, ***p < 0.001