Figure 2.

Effect of rapamycin microparticles and blank microparticles on in vitro glucose-stimulated insulin secretion (GSIS) from islets. (a) Aliquots of 3-5 hand-picked islets were cultured in RPMI-1640 medium in the absence of rapamycin (NT) and in the presence of 20 nM rapamycin microparticles (Rapa MP), blank microparticles (Blk MP) and 20 nM free drug (Control) for 24 h, followed by shifting glucose concentration of culture media from 3 mM to 16 mM. Thirty minutes later, aliquots (100 μl) of media were sampled for insulin measurements using ELISA. *P < 0.05; **P < 0.01; □, basal; ■, stimulated. (b) Fold change in insulin release was compared across the different treatments stated in A). Difference measured was not significant (ns). Bars indicate means ± SEM.