Figure 6.

Islet and re-aggregated cell cluster responses to insulin secretagogues. In order to illustrate the dynamic range of the responses, data were normalized to the baseline (0 drug) level. (A) Carbachol elicited a strong response from rat islets and human re-aggregated cell clusters with a threshold at 3.16 nM. There was no measurable response from native human islets. (B) Caffeine stimulated a similar response in rat islets and human islet clusters with thresholds at 1-3mM. Secretion from human re-aggregated clusters declined at 10 mM caffeine. *P < 0.05. **P < 0.01, significantly below baseline.