Abstract
The primordial cord and the primitive, single and primordial islets present in the 3 earliest stages of the developing endocrine pancreas of sea bass were studied ultrastructurally. The primordial cord consisted of type I and II cells and was included in the gut. Besides these cell types, X cells were seen in the primitive islet. The single islet was made up of type I, II, III and IV cells. A correlation between these endocrine cell-types and cells previously identified immunocytochemically, was established. Type I, II, III and IV cells, correlated respectively with SST-25-, insulin-, SST-14- and glucagon-immunoreactive cells, and could be related to the D1, B, D2 and A cells, respectively, of older larvae and adult sea bass. Each cell type shows characteristic secretory granules from its first appearance. A progressive development of the organelles and an increase in the number and size of the secretory granules, whose ultrastructure also varied, was observed in the endocrine cells of the primordial cord and the succeeding islets. In 25-day-old larvae at the beginning of the fourth developmental stage, the primordial islet, the first ventral islet found, was close to a pancreatic duct and blood vessel, and consisted of type I and II cells whose ultrastructure was similar to that of the type I and II cells in the primordial cord. These data suggest a ductular origin for the pancreatic endocrine cells in the ventral pancreas. It is suggested that although endocrine cells undergo mitosis, their increase in number during the earliest development stages is principally due to the differentiation of surrounding cells.
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References
Agulleiro B, Lozano MT, Abad ME, García Hernández MP (1993) Electron-microscopic immunocytochemical study of the endocrine pancreas of sea bass (Dicentrarchus labrax L). Cell Tissue Res 274:303–314
Agulleiro B, García Hernández MP, Lozano MT (1994) Ontogeny of the endocrine pancreas in sea bass (Dicentrarchus labrax): an ultrastructural study. II. The big and secondary islets. Cell Tissue Res 276:323–331
Alpert S, Hanahan D, Teitelman G (1988) Hybrid insulin genes reveal a developmental lineage for pancreatic endocrine cells and imply a relationship with neurons. Cell 53:295–308
Beccaria C, Díaz JP, Gabrion J, Connes R (1990) Maturation of the endocrine pancreas in the sea bass, Dicentrarchus labrax L. (Teleostei): an immunocytochemical and ultrastructural study. Gen Comp Endocrinol 78:80–92
Bencosme SA, Meyer J, Bergman BJ, Martínez-Palomo A (1965) The principal islet of bullhead fish (Ictalurus nebulosus). A correlative light and electron microscopic study of islet cells and of their secretory granules isolated by centrifugation. Rev Can Biol 24:141–154
Bonner-Weir S (1988) Morphological evidence for pancreatic polarity of cell within islets of Langerhans. Diabetes 37:616–621
Calderón F (1988) Estudio immunocitoquímico y ultraestructural del páncreas endocrino de Gallus gallus en distintas etapas del desarrollo embrionario y en la eclosión. Doctoral thesis, Faculty of Medicine, University of Murcia
Calvert R (1978) Sequential differentiation of intestinal endocrine cells in the fetal mouse. Cell Tissue Res 192:267–276
Carrillo M, Zanuy S, Duve H, Thorpe A (1986) Identification of hormone-producing cells of the endocrine pancreas of the sea bass, Dicentrarchus labrax, by ultrastructural immunocyto-chemistry. Gen Comp Endocrinol 61:287–301
D'Agostino J, Field JB, Frazier ML (1985) Ontogeny of immunoreactive insulin in the fetal bovine pancreas. Endocrinology 116:1108–1116
Dieterlen-Lievre F (1965) Etude morphologique et expérimentale de la différentiation du pancréas chez l'embryon de poulet. Bull Biol Fr Belg 99:3–116
Epple A, Brinn JE (1987) The comparative physiology of the pancreatic islets. Springer, Berlin Heidelberg
García Hernández MP, Agulleiro B (1992) Ontogeny of the endocrine pancreas in sea bass (Dicentrarchus labrax). An immunocytochemical study. Cell Tissue Res 270:339–352
García Hernández MP, Lozano MT, Agulleiro B (1994) Ontogeny of some endocrine cells of the digestive tract in sea bass (Dicentrarchus labrax L.): an immunocytochemical study. Cell Tissue Res (in press)
Gómez Dumm CL, Galeano AM, Genoro S, Gagliardino JJ (1987) Appearance of immunoreactive endocrine cells during the development of the rat pancreas, with special reference to polypeptide-secreting cells. Acta Anat (Basel) 130:158–162
Hashimoto T, Kawano H, Daikoku S, Shima K, Taniguchi H, Baba S (1988) Transient coappearance of glucagon and insulin in the progenitor cells of the rat pancreatic islets. Anat Embryol (Berl) 178:489–497
Jost A (1977) Le rôle des hormones foetales dans la croissance du foetus. J Physiol (Paris) 73:877–890
Kaung HC (1983) Changes of pancreatic beta cell population during larval development of Rana pipiens. Gen Comp Endocrinol 49:50–56
Klein C (1977) Ultrastructural and cytochemical bases for the identification of cell types in the endocrine pancreas of teleosts. Int Rev Cytol 6:290–346
Krijger RR, Aanstoot HJ, Kranenburg G, Reinhard M, Visser WJ, Bruining GJ (1992) The midgestational human fetal pancreas contains cells coexpressing islet hormones. Dev Biol 153:368–375
Like AA, Orci L (1972) Embryogenesis of the human pancreatic islets: a light and electron microscopic study. Diabetes 21:511–534
Lukinius A, Ericsson JLE, Grimelius L, Korsgren O (1992) Ultrastructural studies of the ontogeny of fetal human and porcine endocrine pancreas, with special reference to colocalization of the four major islet hormones. Dev Biol 153:373–385
Melmed RN (1979) Intermediate cells of the pancreas. An appraisal. Gastroenterology 76:196–201
Pictet R, Rutter WJ (1972) Development of the embryonic endocrine pancreas. In: Freinkel N, Steiner DF (eds) Endocrine pancreas. Handbook of physiology, vol 1. Williams and Wilkins, Baltimore, pp 25–66
Pictet R, Clark WR, Williams RH, Rutter WJ (1972) An ultrastructural analysis of the developing embryonic pancreas. Dev Biol 29:436–467
Przybylski RJ (1967) Cytodifferentiation of the chick pancreas I. Ultrastructure of the islet cells and the initiation of granule formation. Gen Comp Endocrinol 8:115–128
Rall L, Pictet R, Williams R, Rutter W (1973) Early differentiation of glucagon-producing cells in embryonic pancreas: a possible developmental role for glucagon. Proc Natl Acad Sci USA 70:3478–3482
Rhoten WB, Hall CE (1982) An immunocytochemical study of the cytogenesis of pancreatic endocrine cells in the lizard, Anolis carolinensis. Am J Anat 163:181–193
Rombout JHWM, Rademakers LHPM, Hees JP van (1979) Pancreatic endocrine cells of Barbus conchonius (Teleostei, Cyprinidae), and their relation to the enteroendocrine cells. Cell Tissue Res 203:9–23
Stipp A, Ferri S, Sesso A (1980) Fine structural analysis of a teleost exocrine pancreas cellular components: a freeze-fracture and transmission electron microscopic study. Anat Anz 147:60–75
Stockdale RE, Holtzer H (1961) DNA synthesis and myogenesis. Exp Cell Res 24:508–520
Wages DW, Munger BL (1977) Unique cytologic parameters of perinatal pancreatic islets. Anat Rec 187:739
Watanabe T, Paik YK, Yasuda M (1975) Fine structure of the pancreatic islets in domestic fowl with special reference to the cell type and secretion. Arch Histol Jap 38:259–274
Wessells NK (1964) DNA synthesis, mitosis and differentiation in pancreatic acinar, cells in vitro. J Cell Biol 20:415–433
Young RW (1962) Cell proliferation and specialization during endochondral osteogenesis in young rats. J Cell Biol 14:357–370
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García Hernández, M.P., Lozano, M.T. & Agulleiro, B. Ontogeny of the endocrine pancreas in sea bass (Dicentrarchus labrax): an ultrastructural study. I. The primordial cord and the primitive, single and primordial islets. Cell Tissue Res 276, 309–322 (1994). https://doi.org/10.1007/BF00306116
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DOI: https://doi.org/10.1007/BF00306116