Ultrastructure of the midgut endocrine cells in Melipona quadrifasciata anthidioides (Hymenoptera, Apidae)

Universidade Federal do Rio de Janeiro, Brazil.
Brazilian Journal of Biology (Impact Factor: 0.78). 12/2003; 63(4):683-90. DOI: 10.1590/S1519-69842003000400015
Source: PubMed


In this study we describe the ultrastructure of the endocrine cells observed in the midgut of M. quadrifasciata anthidioides. This bee has two types of endocrine cells, which are numerous on the posterior midgut region. Cells of the closed type are smaller and have irregular secretory granules with lower electrondensity than those of the open cell type. The open cell type has elongated mitochondria mainly on the basal area, where most of the secretory granules are also found. Besides the secretion granules and mitochondria, endocrine cells in this species have well-developed autophagic vacuoles and Golgi complex elements.

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Available from: José Eduardo Serrão, May 23, 2014
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    • " s & Beauvillain 1988 ; Montuenga et al . 1989 ; Punin et al . 2000 ; Neves et al . 2002 ) . While no markers for biologi - cally active peptides such as hormones were used in this study , the ultrastructure of the secretory cells resembles that of hexapodan endocrine cells ( Andriè s & Tramu 1985 ; Raes & Verbeke 1994 ; Leite & Evangelista 2001 ; Neves et al . 2003 ) . While the midgut epithelium of millipedes is sur - rounded by a layer of cells called " liver , " " hepatic cells , " or " hepatic tissue " that accumulate sub - stances which are carried to the hemolymph to be excreted ( Fontanetti et al . 2001 ; de Godoy & Fonta - netti 2010 ) , such cells have not been described in centipedes . T"
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    • "ent membrane, another type of epithelium which could be observed is regenerative cells; their terminals did not reach the lumen, these were in agreement with (Cruz-Landim, 1985; Serrao and Cruz-Landim, 1995b and Cruz-Landim and Cavalcante, 2003). While the midgut endocrine cells of insects, generally, are not easily identified by light microscope (Neves et. al., 2003). The columnar epithelial cells are the functional, digestive cells; regenerative cells serve to regenerate the damaged functional cells (Serrao and Cruz-Landim, 1995a and Cruz-Landim et. al., 1996)."

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