ISSN:
0003-276X
Schlagwort(e):
Life and Medical Sciences
;
Cell & Developmental Biology
Quelle:
Wiley InterScience Backfile Collection 1832-2000
Thema:
Medizin
Notizen:
The endocrine pancreas of the Coturnix quail consists of two major islet configurations. Islets containing B and D cells are found in all four lobes of the pancreas, but islets consisting of A and D cells occur with regularity only in the third and splenic lobes. Pancreatic islets comprise only a small percentage of the tissue volume in the ventral, dorsal and third lobes. In the splenic lobe, however, one or more A islets surrounded by numerous small B islets may constitute more than 50% of the total cellular mass.Secretory granules of the B cells are aldehyde fuchsin-positive and show three distinct profiles at the ultrastructural level. The PTAH-positive A granules are usually round or teardrop shaped and are of uniform electron density. D cells are argyrophilic; their secretory granules are of heterogeneous densities. These cells are located at the peripheries of the B islets, but are freely dispersed in the A islets. At the electron microscopic level, Type IV cells, previously not reported in avian islets, are found mainly in the A islets of this species. This unusual cell type contains granules of differing densities, but, unlike those of the D cell, they are often rod-shaped and biconcave in profile.Because of the distinct segregation of islet types, and the peculiar arrangement of the D and Type IV cells within the two kinds of islets, it is suggested that the Japanese quail may serve as a model for investigations of avian islet function.
Materialart:
Digitale Medien
URL:
http://dx.doi.org/10.1002/ar.1091780305
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