摘要：D -Aspartate is present in the central nervous system and various endocrine organs, and modulates their neuroendocrine function. In islets of Langerhans, α and β cells contain D -aspartate. Here we show that INS-1E clonal β cells contain the highest amount of D -aspartate. Immunohistochemical analysis with specific antibodies against D -aspartate indicated that D -aspartate is co-localized with insulin. Upon the addition of K+, both D -aspartate and insulin are secreted from the cells in a Ca2+-dependent manner. A Ca2+ ionophore, A23187, also triggers the release of D -aspartate and insulin in the presence of Ca2+. Bafilomycin A1, a specific inhibitor of V-ATPase and V-ATPase-linked secondary transport, inhibits the secretion of D -aspartate. These results support the idea that D -aspartate is present in insulin-containing secretory granules and co-secreted with insulin through exocytosis.
关键词：D -aspartate;islet of Langerhans;α cell;β cell;insulin
