Figure 4.

Insulin concentration in the media of BRIN-BD11 cells, after chronic (a) and acute (b) insulin secretion assay. (a) Chronic insulin secretion: 1 day after seeding of BRIN-BD11 cells in 96-well plates (5 × 10³ cells/well), the cells were incubated for another 24 h in their regular growth medium, in the absence or presence of porcine pancreatic amylase (a) (final concentrations of 16, 32, and 64 μg/ml, resulting in a final activity of 35.9, 69.2, and 114.5 U/l, respectively). Sterile 0.9% NaCl was used as a vehicle. Data are the mean of 32 independent cell cultures (for each treatment) from two independent experiments. (b) Acute insulin secretion: BRIN-BD11 cells were seeded in 24-well plates (1.5 × 10⁵ cells/well) in the routine medium. After 24 h of incubation, the cells were starved for 40 minutes in bKRBB. The cells were then challenged with sKRBB, in the presence or absence of 32 μg/ml porcine pancreatic amylase (a) for 20 min. Sterile 0.9% NaCl was used as a vehicle. Data are the mean of 12 independent cell cultures (for each treatment) from two independent experiments. bKRBB: basal medium; sKRBB: stimulative medium.