Fish gills alterations as potential biomarkers of environmental quality in a eutrophized tropical river in south-eastern Brazil.

Gill anomalies in three common fish species of different taxonomic order, habitat dwelling and feeding habits (one Characiformes, Oligosarcus hepsetus; one Siluriformes, Hypostomus auroguttatus; and one Perciformes, Geophagus brasiliensis) from a eutrophized tropical river in south-eastern in Brazil were compared. The aim of this study was to search for sentinel species that could be used as potential biomarkers of environmental quality. Most fish had gills with histological changes, namely epithelial lifting, interstitial oedema, leucocyte infiltration, hyperplasia of the epithelial cells, lamellar fusion, vasodilatation and necrosis. On the other hand, lamellar blood congestion and lamellar aneurysm, which are more serious and often irreversible changes, were recorded for the water column carnivorous O. hepsetus and, to a lesser extent, for the bottom-dwelling detritivorous H. auroguttatus. A histopathological alteration index (HAI) based on the occurrence and severity of gills anomalies indicated that O. hepsetus (mean score = 11.4) had significantly higher values (Kruskall-Wallis H(2,41) = 15.95, P = 0.0003) compared with G. brasiliensis (mean score = 7.0). Overall, the omnivorous G. brasiliensis had comparatively lesser occurrence of most gill anomalies compared with other two species, being less suitable as biomarker of environmental quality. In contrast, the water column-dweller O. hepsetus (water column) and the bottom-dweller H. auroguttatus had gills most susceptible to changes, making them more suitable for using as histological biomarkers of the environmental quality in entrophized tropical rivers.

Immunocytochemical study of the distribuition of endocrine cells in the pancreas of the Brazilian sparrow species Zonotrichia Capensis Subtorquata (Swaison, 1837)

In the present study, we investigated types of pancreatic endocrine cells and its respective peptides in the Brazilian sparrow species using immunocytochemistry. The use of polyclonal specific antisera for somatostatin, glucagon, avian pancreatic polypeptide (APP), YY polypeptide (PYY) and insulin, revealed a diversified distribution in the pancreas. All these types of immunoreactive cells were observed in the pancreas with different amounts. Insulin- Immunoreactive cells to (B cells) were most numerous, preferably occupying the central place in the pancreatic islets. Somatostatin, PPA, PYY and glucagon immunoreactive cells occurred in a lower frequency in the periphery of pancreatic islets.

Os tipos de células endócrinas e seus respectivos peptídeos reguladores foram estudados imunocitoquimicamente no pâncreas do tico-tico, espécie Zonotrichia capensis subtorquata, empregando-se o método imunocitoquímico ABC - Peroxidase (Complexo Avidina - Biotina - Peroxidase) e anti-soros específicos para somatostatina, ao glucagon, ao polipeptídeo pancreático aviário (PPA), ao polipeptídeo YY (PYY) e à insulina. Todos estes tipos de células imunorreativas foram observadas no pâncreas em quantidades diferentes. As células imunorreativas à insulina (células B) foram as mais numerosas, ocupando preferencialmente, a região central das ilhotas pancreáticas. As células endócrinas imunorreativas à somatostatina, PPA, PYY e glucagon localizaram-se predominantemente na periferia das ilhotas.

Immunocytochemical study of the distribuition of endocrine cells in the pancreas of the Brazilian sparrow species Zonotrichia Capensis Subtorquata (Swaison, 1837).

In the present study, we investigated types of pancreatic endocrine cells and its respective peptides in the Brazilian sparrow species using immunocytochemistry. The use of polyclonal specific antisera for somatostatin, glucagon, avian pancreatic polypeptide (APP), YY polypeptide (PYY) and insulin, revealed a diversified distribution in the pancreas. All these types of immunoreactive cells were observed in the pancreas with different amounts. Insulin-Immunoreactive cells to (B cells) were most numerous, preferably occupying the central place in the pancreatic islets. Somatostatin, PPA, PYY and glucagon immunoreactive cells occurred in a lower frequency in the periphery of pancreatic islets.