TY - JOUR AU - Namkung, Yoon AU - Skrypnyk, Nataliya AU - Jeong, Myung-Jin AU - Lee, Taehoon AU - Lee, Myung-Shik AU - Kim, Hyung-Lae AU - Chin, Hemin AU - Suh, Pann-Ghill AU - Kim, Sung-Sook AU - Shin, Hee-Sup T1 - Requirement for the L-type Ca2+ channel α1D subunit in postnatal pancreatic β cell generation PY - 2001/10/01/ AB - Pancreatic β cells are the source of insulin, which directly lowers blood glucose levels in the body. Our analyses of α1D gene-knockout (α1D–/–) mice show that the L-type calcium channel, α1D, is required for proper β cell generation in the postnatal pancreas. Knockout mice were characteristically slightly smaller than their littermates and exhibited hypoinsulinemia and glucose intolerance. However, isolated α1D–/– islets persisted in glucose sensing and insulin secretion, with compensatory overexpression of another L-type channel gene, α1C. Histologically, newborn α1D–/– mice had an equivalent number of islets to wild-type mice. In contrast, adult α1D–/– mice showed a decrease in the number and size of islets, compared with littermate wild-type mice due to a decrease in β cell generation. TUNEL staining showed that there was no increase in cell death in α1D–/– islets, and a 5-bromo-2′ deoxyuridine-labeling (BrdU-labeling) assay illustrated significant reduction in the proliferation rate of β cells in α1D–/– islets. JF - The Journal of Clinical Investigation JA - J Clin Invest SN - 0021-9738 DO - 10.1172/JCI13310 VL - 108 IS - 7 UR - https://doi.org/10.1172/JCI13310 SP - 1015 EP - 1022 PB - The American Society for Clinical Investigation ER -