[The tongue mast cells of Bufo marinus L. toad: characterization of glycoconjugates with conventional and lectin methods]. / Los mastocitos de la lengua del sapo Bufo marinus L.: caracterizacion histoquimica de glicoconjugados con tecnicas convencionales y con lectinas.

Mast cell populations in mammals have been recognized as morphologically and functionally heterogeneous. In situ characterization of these cell type carbohydrates with conventional histochemical techniques and with lectin histochemistry has not been afforded in amphibian species. Different conventional staining methods for complex carbohydrates and 18 different, biotin or peroxidase conjugated, lectins were used in paraffin embedded Rossman fluid-fixed sections of mid-central region of the toad tongue. Conventional carbohydrate histochemistry showed a single type of mast cells with a variable concentration of highly sulphated glycosaminoglycans. Lectin histochemistry showed partial heterogeneity in the mast cell population. Most cells contain N-linked and O-linked oligosaccharides with variable quantities of Man but high of GlcNAc and terminal Gal-beta (1,3)-GaINAc residues. A considerable number of mast cells showed proteins or oligosaccharides with terminal sialic acid residues but only few mast cells contain terminal fucose. Discussion is made comparing these results with similar histochemical studies and with functional experimental studies performed in human and rat mast cells.

[Suggestive evidences for a microanatomical relationship between mast cells and nerve in the tongue of the toad Bufo marinus demonstrated by means of high resolution light microscopy]. / Evidencias que sugieren una asociación microanatómica mastocito-nervio en la lengua del sapo Bufo marinus demostradas mediante microscopia de luz de alta resolucion.

Mast cells are connective tissue cells, present in all vertebrates and characterized by the metachromatic stain of their granules. Nowadays mast cells have been recognized as a potent cellular source of multiple cytokines, suggesting an important role in immunoregulation and host defense. These cells have been described as preferentially located around blood vessels but more recently close spatial relationship between mast cells and nerves has been reported mostly in mammalian species. The microanatomy of nerve tissue and associated mast cells in the toad Bufo marinus tongue have been studied here by means of high resolution light microscopy. Mast cell population was identified by the metachromatic staining of their cytoplasm granules in Epon embedded semithin sections counterstained with Toluidine Blue and Azure A. Numerous mast cells were observed scattered throughout the submucosal region, adjacent and/or within of nerve bundles and nerve ganglia, near skeletal muscle fibers and adjacent of blood vessels. Additionally, mast cells adjacent to single but conspicuous myelinated nerve fibers were seen under endothelia of lymphatic vessels wall and this is apparently a unreported event. Results suggest nerve-mast cell associations are functionally important in the toad tongue.

Los mastocitos de la lengua del sapo Bufo marinus L: caracterizacion histoquimica de glicoconjugados con tecnicas convencionales y con lectinas / The tongue mast cells of Bufo marinus L. toad: characterization of glycoconjugates with conventional and lectin methods

Mast cell populations in mammals have been recognized as morphologically and functionally heterogeneous. In situ characterization of these cell type carbohydrates with conventional histochemical techniques and with lectin histochemistry has not been afforded in amphibian species. Different conventional staining methods for complex carbohydrates and 18 different, biotin or peroxidase conjugated, lectins were used in paraffin embedded Rossman fluid-fixed sections of mid-central region of the toad tongue. Conventional carbohydrate histochemistry showed a single type of mast cells with a variable concentration of highly sulphated glycosaminoglycans. Lectin histochemistry showed partial heterogeneity in the mast cell population. Most cells contain N-linked and O-linked oligosaccharides with variable quantities of Man but high of GlcNAc and terminal Gal-beta (1,3)-GaINAc residues. A considerable number of mast cells showed proteins or oligosaccharides with terminal sialic acid residues but only few mast cells contain terminal fucose. Discussion is made comparing these results with similar histochemical studies and with functional experimental studies performed in human and rat mast cells

Evidencias que sugieren una asociacion microanatomica mastocito-nervio en la lengua del sapo Bufo Marinus demostradas mediante microscopia de luz de alta resolucion / Suggestive evidences for a microanatomical relationship between mast cells and nerve in the tongue of the toad Bufo Marinus demonstrated by means of high resolution light microscopy

Los mastocitos son células del tejido conectivo presentes en todos los vertebrados y caracterizados por la coloración metacromática de sus gránulos. Actualmente están reconocidos como potentes productores de múltiples citocinas, sugiriendo un papel importante en la inmunoregulación y en la defensa del hospedador. Estas células han sido descritas preferentemente localizadas alrededor de los vasos sanguíneos pero recientemente se han reportado relaciones espaciales próximas entre mastocitos y nervios mayoritariamente refe-ridos a mamíferos. En este trabajo se estudia, mediante microscopía de luz de alta resolución, la anatomía microscópica de los mastocitos asociados al tejido nervioso, en la lengua del sapo Bufo marinus. La población de mastocitos fue identificada en los cortes semifinos incluidos en Epon por la tinción metacromática de sus gránulos citoplasmáticos al ser contrastados con Azul de Toluidina y Azure A. Se observaron numerosos mastocitos dispersos a través de la región submucosal, adyacentes y/o dentro de paquetes nerviosos y de ganglios nerviosos, cerca de fibras musculares esqueléticas y adyacentes a vasos sanguíneos. Adicionalmente, se observaron mastocitos adyacentes a fibras nerviosas mielínicas conspicuas e individuales, bajo el endotelio de los vasos linfáticos, siendo éste aparentemente, un evento previamente no reportado. Los resultados sugieren que las asociaciones mastocitos-nervios son funcionalmente importantes en la lengua del sapo.