Figure 3

Prior oral treatment with DMA and amiloride enhances insulin secretion in isolated islets from diabetic NON mice: Islets were isolated from diabetic NON mice previously treated with DMA (estimated dose: 1 mg/kg/day) or amiloride (estimated dose: 5 mg/kg/day) in drinking water for a week. Groups of islets were treated with different secretagogues as indicated, and insulin secretion was measured at the end of the 60-minute stimulation period. Prior oral treatment with amiloride derivatives significantly enhances insulin secretion stimulated by each secretagogue. G = mM glucose; αKIC = alpha-ketoisocaproate (20 mM); BCH = 2-amino-bicyclo[2,2,1]heptane-2-carboxylic acid (20 mM); n = 5; * = p < 0.001 and # = p < 0.05, compared with each corresponding untreated control group. Values in the figure are expressed as fractional release (% of total insulin content released over the 60-minute period). The corresponding absolute amounts (ng/ml) for each condition from left to right are: 9.5 ± 1.29, 12.4 ± 3.06, 4.5 ± 1.05, 18.81 ± 2.65, 24.73 ± 1.96, 19.02 ± 3.02, 11.8 ± 1.38, 8.0 ± .66, 7.5 ± 0.96, 5.98 ± 1.48, 9.07 ± 2.1, and 8.92 ± 1.95