LECTIN HISTOCHEMICAL STUDY OF THE GERMINAL EPITHELIUM OF Genypterus blacodes (PINK CUSKEEL)

DÍAZ A, FREIJO, GARCÍA A, PORTIANSKY E, BARBEITO C, MACCHI G

Rosario

Congreso; VII Congreso– XXV Reunión anual de la Sociedad de Biología de Rosario; 2005

Sociedad de Biología de Rosario

The ovary of Genypterus blacodes is typical of teleost fishes. The germinal epithelium borders upon the ovarian lumen. Epithelial cells show morphological changes depending on the maturity stage. During the spawning season the flat squamous epithelium becomes columnar shaped and evidences glicoproteins (GPs) secretion activity. GPs probably form a mucous envelope surrounding the spawned oocytes. The aim of this work is the characterization of the lectinhistochemical pattern of GPs and its distribution in the germinal epithelium during spawning stage. Samples were collected from fishes captured in San Jorge Gulf, fixed in 10% formaldehyde and embedded in parafin. Sections were stained with a battery of biotinilated lectins: Con-A, WGA, DBA, SBA, PNA, RCA- 1 and UEA-1. Diaminobenzidine was used as a cromogen, ABC complex as an amplification system and hematoxylin as a counterstain. The glicocalix of epithelial cells showed a strong staining with Con-A (which binded mannose) and WGA (N-acetyl- glucosamine), but a moderate reaction with N-acetyl-galactosamine binding lectins (DBA, SBA) and fucose binding lectins (UEA-1). Apical cytoplasm showed moderate reaction with Con-A and SBA. Basal cytoplasm showed not reaction. The composition and distribution of GPs secreted by the germinal epithelium during spawning would be related to the physical-chemical properties of the mucus. Moreover they would be also related to functional aspects of the epithelium in oocytes maturation. germinal epithelium borders upon the ovarian lumen. Epithelial cells show morphological changes depending on the maturity stage. During the spawning season the flat squamous epithelium becomes columnar shaped and evidences glicoproteins (GPs) secretion activity. GPs probably form a mucous envelope surrounding the spawned oocytes. The aim of this work is the characterization of the lectinhistochemical pattern of GPs and its distribution in the germinal epithelium during spawning stage. Samples were collected from fishes captured in San Jorge Gulf, fixed in 10% formaldehyde and embedded in parafin. Sections were stained with a battery of biotinilated lectins: Con-A, WGA, DBA, SBA, PNA, RCA- 1 and UEA-1. Diaminobenzidine was used as a cromogen, ABC complex as an amplification system and hematoxylin as a counterstain. The glicocalix of epithelial cells showed a strong staining with Con-A (which binded mannose) and WGA (N-acetyl- glucosamine), but a moderate reaction with N-acetyl-galactosamine binding lectins (DBA, SBA) and fucose binding lectins (UEA-1). Apical cytoplasm showed moderate reaction with Con-A and SBA. Basal cytoplasm showed not reaction. The composition and distribution of GPs secreted by the germinal epithelium during spawning would be related to the physical-chemical properties of the mucus. Moreover they would be also related to functional aspects of the epithelium in oocytes maturation.