title: Pancreatic endocrine cells in sea bass (Dicentrarchus labrax L.) II. Immunocytochemical study of insulin and somatostatin peptides.
abstract: Insulin (INS)- and somatostatin (SST)-immunoreactive cells were demonstrated by light immunocytochemistry in the endocrine pancreas of sea bass (Dicentrarchus labrax). INS-immunoreactive cells were identified using bovine/porcine, bonito, and salmon (s) INS antisera; the immunostaining was abolished when each antiserum was preabsorbed with its respective peptide but not with unrelated peptides. These cells also reacted with mammal (m) SST-28 (4-14) antiserum. The immunoreaction did not change when this antiserum was preabsorbed by bovine INS. INS-immunoreactive cells were located in the central part of the endocrine areas of the principal, intermediate, and small islets. Two SST-immunoreactive cell types (D1 and D2) were revealed. D1 cells, immunoreactive to SST 14 (562) and sSST-25 antisera, were located next to the glucagon-immunoreactive cells in the peripheral part of the endocrine areas. D2 cells, immunoreactive to SST-14 (562), SST-14 (566), and mSST-28 (4-14) antisera, were found in apposition to the INS-immunoreactive cells. The specificity controls showed that D1 cells expressed sSST-25-like peptides, while D2 cells might contain SST-14 and/or mSST-28-like peptides. The close topographic association between the different SST-immunoreactive cells and both glucagon- and insulin-immunoreactive cells might indicate the existence of a specific paracrine regulation of each endocrine cell type in the sea bass endocrine pancreas.
authors.affiliation: Department of Cell Biology, Faculty of Biology, University of Murcia, Spain.
authors.forename: M T
authors.initials: MT
authors.lastname: Lozano
authors.forename: A
authors.initials: A
authors.lastname: Garcia Ayala
authors.forename: M E
authors.initials: ME
authors.lastname: Abad
authors.forename: B
authors.initials: B
authors.lastname: Agulleiro
mesh_terms: D000818:Animals; D001492:Bass / Q000033:anatomy & histology / Q000378:metabolism*; D002417:Cattle; D005260:Female; D005399:Fishes; D007106:Immune Sera / Q000276:immunology; D007124:Immunoenzyme Techniques; D007328:Insulin / Q000032:analysis* / Q000276:immunology; D007515:Islets of Langerhans / Q000737:chemistry* / Q000166:cytology; D008297:Male; D013004:Somatostatin / Q000032:analysis*; D013552:Swine
chemical_list: D007106:Immune Sera; D007328:Insulin; D013004:Somatostatin