Insulin levels and insulin secretion by pancreatic islets of male SHAM-P1, PINX-P1 and PM-P1 rats.

<p>Male offspring were decapitated at ZT10, the pancreata were perfused with collagenase and the islets were isolated. After isolation, groups of five islets were initially incubated for 45 min at 37°C in Krebs–bicarbonate buffer containing 5.6 mM glucose and equilibrated with 95% O₂–5% CO₂, pH 7.4. The solution was then replaced with fresh Krebs–bicarbonate buffer, and the islets were incubated for an additional 1 h with medium containing 5.6, 8.3, 11.1 or 16.7 mM glucose. Insulin was quantified by RIA in the supernatant (<b>A</b>). Serum from the rats was used to determine circulating insulin levels (<b>B</b>). Open bars are SHAM-P1, black bars are PINX-P1 and grey bars are PM-P1. The data represent the cumulative insulin secretion over 1 h and are given as the mean ± SE. *P<0.05 vs. SHAM-P1 with 5.6 mM glucose; #P<0.05 vs. PM-P1 with 5.6 mM glucose; &P<0.05 vs. SHAM-P1 (n=5 for insulin secretion and insulin levels).