92 research outputs found
Glycohistochemical investigation on canine and feline zonae pellucidae of preantral and antral oocytes
Glycoconjugate modifications were analysed in the zona pellucida during development of oocytes in dog and cat using conventional histochemical staining methods with or without previous carbohydrate digestion. A series of lectins combined with desulphation and sialic acid degradation were applied. No differences were observed between dog and cat follicles using conventional histochemical staining methods. In both species, the zona pellucida and follicular fluid/intercellular matrix strongly reacted with PAS and high iron diamine stain (HID) and reacted moderately with low iron diamine stain (LID). Treatment with testicular hyaluronidase, chondroitinase ABC, chondroitinase AC and chondroitinase B treatment diminished HID and LID positivity of follicular fluid and intercellular matrix. Lectins that gave the most intense staining of the zona pellucida of both species were SBA, PNA, RCA-I, GSA-IB4 and WGA, indicating the presence of beta-D-GalNAc, D-Gal and GlcNAc residues. Sulpho- and asulpho-carbohydrates were identified in terminal and/or subterminal positions linked to sialic acid residues. In conclusion, the results indicate that glycosaminoglycans are not present in the zona pellucida of both species. Differences were observed in carbohydrate residues and in their spatial distribution, depending on species and developmental stage of the follicles. The similarity in lectin affinity between ooplasm and zona pellucida of oocytes present in follicles at different stages of development confirm the involvement of oocytes in zona pellucida production
Glycoconjugates in small antral ovarian follicles of the river buffalo (Bubalus bubalis L.)
Types and distribution patterns of glycoconjugates in antral ovarian follicles were investigated in the buffalo, using periodic-acid Schiff (PAS), high iron diamine (HID), low ion diamine (LID) and lectin histochemical staining methods. HID and LID staining procedures were preceded in some cases by digestion with testicular hyaluronidase, Streptomyces hyaluronidase, chondroitinase ABC and heparitinase (heparinase III). Lectin staining was performed with the use of 12 horseradish peroxidase (HRP) lectin conjugates. Some lectin staining procedures were preceded by neuraminidase digestion and saponification. Large amounts of isomeric chondroitin sulphates and a minor quantity of heparan sulphate and hyaluronic acid and/or chondroitin were found in follicular fluid. Lectin staining of buffalo follicular fluid revealed glycoconjugates with different glucidic determinants such as beta-N-acetylgalactosamine, beta-galactose-(1-3)-N-acetylgalactosamine, beta-galactose-(1-4)-N-acetylglucosamine, N-acetylglucosamine, alpha-fucose and alpha-glucose/alpha-mannose, and sialic acid residues. Glycosaminoglycans were absent in the zona pellucida of oocytes in small antral follicles. Acidic glycoconjugates in the zona pellucida were caused by sulphated groups and sialic acid residues. Our data show few internal glucidic residues, such as N-acetylglucosamine in the buffalo zona pellucida but many subterminal beta-N-acetylgalactosamine, alpha- and beta-galactose determinants masked by sialic acids. These findings demonstrate that buffalo follicular fluid has a very heterogeneous composition that is similar to that found in small and large bovine follicles. No differences in composition of the follicular fluid were observed in the follicles examined
Chromosomal analysis of embryos produced by artificially inseminated superovulated cattle
International audienc
Application of the cDNA-AFLP method for studying gene expression in Fibrobacter succinogenes S85 exposed to 134.2 kHz electromagnetic field
AbstractMany biological effects related to the exposure of cells and tissues to electromagnetic fields have been reported in the literature, including those influencing DNAs and RNAs structure and ..
Immunogold study on lectin binding in the porcine zona pellucida and granulosa cells
An ultrastructural localization of lectin receptors on the zona pellucida (ZP) of porcine antral oocytes and on the granulosa cells was performed using a panel of horseradish peroxidase- labelled lectins in conjunction with antiperoxidase antibody and protein A-gold. In some cases, lectin incubation was preceded by sialidase digestion. WGA-, Con-A-, UEA-I-, RCA-I-, PNA- and SBA-reactive sites were distributed differently in the porcine ZP. Sialidase digestion increased the positivity obtained with RCA-I and it was necessary to promote PNA and SBA reactivity. These results indicated that the ZP contained N-acetylglucosamine, a-mannose, a- fucose, b-Gal-(1-4)GlcNAc, b-Gal- (1-3)GalNAc, b-GalNAc and sialic acid residues. We also observed the presence of vesicles in both the ooplasm and granulosa cells, showing a similar lectin binding pattern to that of the ZP, thus suggesting that the oocyte and granulosa cells are the site of synthesis of ZP glucidic determinants
Characterization of glycoconjugates in the secretory epithelium of the equine ampulla ductus deferentis
The present work was undertaken to
determine the glycoconjugates secreted by the
epithelium of the equine ampulla ductus deferentis,
using conventional (PAS, AB pH 2.5, AB pH 1.0) and
lectin histochemical procedures in conjunction with
enzymatic digestion and chemical treatment. The
presence of abundant apical cytoplasmic blebs suggests
that the equine ampulla secretes its products mainly in
an apocrine manner. Glandular cells secrete neutral and
acidic sialylated glycoconjugates as revealed by
conventional histochemical procedures. Lectin
histochemistry helped us to discover the following
histological positive sites: the mucosal cells, the
glandular epithelial cells, the apical cytoplasmic blebs
and the basal cells. The ampullary secretions contained
both glycoproteic material (revealed by Con-A-, LCA-,
GSA-II-, WGA-, RCA-I- positivity) and sialomucins
(evidenced by the reactivity of GSA-II, SBA, PNA and
RCA-I after sialidase digestion) having different
functional roles. The mucosal cells reacted with Con-A,
LCA, and also with sialidase/GSA-II-, SBA-, PNA-, and
RCA-I sequences, contributing to the chemical heterogeneity of ampullary secretions. DBA lectin was a
specific marker for basal cells.
The results obtained were compared with our
previous findings regarding the differences in the lectin
binding pattern of the plasma-membrane of equine
sperm collected from epididymal cauda and the ampulla
ductis deferentis. Our results support other studies that
indicate that ampullary secretions are involved in
altering the plasma-membrane glycoconjugates of
spermatozoa, contributing to their maturation
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