Figure 2. (A) Relative insulin secretion of young porcine endocrine pancreatic islets after 1 h stimulation with low glucose concentration (LG, 2.8 mM), high glucose concentration (HG, 28 mM), high glucose concentration + 3-isobutyl-1-methylxanthine (IBMX) (HI, 28 mM + IBMX) and a second low glucose concentration (LG2, 2.8 mM) concentration. Insulin secretion of islets in TCPS/fibrin was normalized to the insulin secretion of islets in TCPS/fibrin with no H₂O₂ in response to low glucose concentration. (B) Three repeats of a glucose-stimulated insulin secretion assay with LG, HG, HI and a final LG. Shown are the insulin contents in the media (microgram per liter) of porcine pancreatic islets (200 IEQ) cultured on TCPS (T) or in fibrin gels (F) with 0, 10 or 100 µM H2O2.’*’ represents a value of P < 0.05, ‘ns‘ means no statistical significance.