Biomaterial Database

Increased islet volume but unchanged islet number in ob/ob mice. 2003

Troels Bock, and Bente Pakkenberg, and Karsten Buschard

H:S Bartholin Institute, Copenhagen University Hospital, Copenhagen, Denmark. tbock@post12.tele.dk

It is important for our understanding of the pancreatic islets to study whether new islets are able to form in the intact pancreas. We developed a new method to determine the total number and the mean volume of the pancreatic islets, and we used this method to study the expansion of the islet mass in ob/ob mice (n = 8), using ob/+ mice (n = 8) as controls. The total islet volume was increased by a factor of 3.6 in ob/ob mice compared with ob/+ mice, whereas, importantly, the total number of islets did not differ among ob/ob mice and ob/+ mice (3,193 +/- 160 islets in ob/ob mice vs. 3,184 +/- 142 islets in ob/+ mice, P = 0.97). The coefficient of variation in the volume distribution of islets was equal in the two groups, showing that in ob/ob mice, the existing islets expand their volume by the same proportion, without a net formation of new islets. We suggest that the pancreatic islets should be considered as anatomically such complex structures that islet neogenesis does not spontaneously occur in an intact pancreas. Cells within the existing islets are presumably the most important sources for islet cell hyperplasia during expansion of the total islet mass.

UI	MeSH Term	Description	Entries
D007515	Islets of Langerhans	Irregular microscopic structures consisting of cords of endocrine cells that are scattered throughout the PANCREAS among the exocrine acini. Each islet is surrounded by connective tissue fibers and penetrated by a network of capillaries. There are four major cell types. The most abundant beta cells (50-80%) secrete INSULIN. Alpha cells (5-20%) secrete GLUCAGON. PP cells (10-35%) secrete PANCREATIC POLYPEPTIDE. Delta cells (~5%) secrete SOMATOSTATIN.	Islands of Langerhans,Islet Cells,Nesidioblasts,Pancreas, Endocrine,Pancreatic Islets,Cell, Islet,Cells, Islet,Endocrine Pancreas,Islet Cell,Islet, Pancreatic,Islets, Pancreatic,Langerhans Islands,Langerhans Islets,Nesidioblast,Pancreatic Islet
D008820	Mice, Obese	Mutant mice exhibiting a marked obesity coupled with overeating, hyperglycemia, hyperinsulinemia, marked insulin resistance, and infertility when in a homozygous state. They may be inbred or hybrid.	Hyperglycemic Mice,Obese Mice,Mouse, Hyperglycemic,Mouse, Obese,Hyperglycemic Mouse,Mice, Hyperglycemic,Obese Mouse
D010179	Pancreas	A nodular organ in the ABDOMEN that contains a mixture of ENDOCRINE GLANDS and EXOCRINE GLANDS. The small endocrine portion consists of the ISLETS OF LANGERHANS secreting a number of hormones into the blood stream. The large exocrine portion (EXOCRINE PANCREAS) is a compound acinar gland that secretes several digestive enzymes into the pancreatic ductal system that empties into the DUODENUM.
D012016	Reference Values	The range or frequency distribution of a measurement in a population (of organisms, organs or things) that has not been selected for the presence of disease or abnormality.	Normal Range,Normal Values,Reference Ranges,Normal Ranges,Normal Value,Range, Normal,Range, Reference,Ranges, Normal,Ranges, Reference,Reference Range,Reference Value,Value, Normal,Value, Reference,Values, Normal,Values, Reference
D002452	Cell Count	The number of CELLS of a specific kind, usually measured per unit volume or area of sample.	Cell Density,Cell Number,Cell Counts,Cell Densities,Cell Numbers,Count, Cell,Counts, Cell,Densities, Cell,Density, Cell,Number, Cell,Numbers, Cell
D000818	Animals	Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA.	Animal,Metazoa,Animalia
D051379	Mice	The common name for the genus Mus.	Mice, House,Mus,Mus musculus,Mice, Laboratory,Mouse,Mouse, House,Mouse, Laboratory,Mouse, Swiss,Mus domesticus,Mus musculus domesticus,Swiss Mice,House Mice,House Mouse,Laboratory Mice,Laboratory Mouse,Mice, Swiss,Swiss Mouse,domesticus, Mus musculus