Neonatal beta cells lack the specialized metabolic phenotype of mature beta cells

Fetal and neonatal beta cells have poor glucose-induced insulin secretion and only gain robust glucose responsiveness several weeks after birth. This unresponsiveness may be due to a generalized immaturity of the metabolic pathways normally found in beta cells. Gene expression profile of neonatal (1 day old) and young adult (6 weeks old) Sprague-Dawley rat islets were evaluated and compared. Frozen sections were obtained from pancreases of neonatal (1 day old) and young adult (6 weeks old) Sprague-Dawley rats. The beta cell enriched cores of the islets were excised using laser capture microdissection. RNA was extracted, amplified and subjected to microarray analysis.