Berna Güney Saruhan

Immunolocalization of vascular endothelial growth factor, its receptors (flt1/fms, flk1/KDR, flt4) and vascular endothelial growth inhibitor in the bitch uterus during the sexual cycle

Angiogenesis is regulated by proangiogenic and antiangiogenic factors. Vascular endothelial growth factor (VEGF) is a prime proangiogenic regulator, whereas vascular endothelial growth inhibitor (VEGI) is a specific antiangiogenic cytokine. To clarify temporal changes in the localization of pro-angiogenic and anti-angiogenic factors in the uterus of normal bitches during the proestrus, estrus, diestrus and anestrus phases of the estrous cycle, the expressions of VEGF and its receptors (flt1/fms, flk1/KDR and flt4) and their correlation with VEGI were analyzed using immunohistochemistry. Uteruses were collected after ovariohysterectomy. Immunohistochemical staining was evaluated semi-quantitatively by an immunohistochemical total score consisting of the sum of the intensity and proportional scores. The results in the bitch uterus demonstrated that positive immunohistochemical staining was found exclusively in the cytoplasm and apical membrane of luminal and glandular epithelial, stromal and smooth muscle cells and nuclear staining was observed in the flt1/fms, flk4 and VEGI during proestrous and estrous. Semi-quantitative analyses revealed that the total score for VEGF in the glandular epithelial cells was significantly higher than that of luminal, endometrial stromal and myometrial smooth muscle cells during proestrous (p<0.05). The total score for flk1/KDR and flt4 in the glandular epithelium was also significantly higher than that of endometrial stromal cells during proestrous, whilst the total score for flt1/fms in the glandular epithelium was significantly higher than that of endometrial stromal cells during anestrus (p<0.05). We conclude that, in the bitch uterus, cyclic changes may be precisely regulated by the combined functions of VEGF family members, angiogenic VEGF and VEGF receptors, and the angiogenesis inhibitor VEGI.

The expression of epidermal growth factor receptors and their ligands (epidermal growth factor, neuregulin, amphiregulin) in the bitch uterus during the estrus cycle

In order to study the possible role of EGFR receptors in the bitch reproductive process, we have analyzed the expression pattern and localization of EGFR receptors and some of their ligands epidermal growth factor (EGF), neuregulin (NRG), amphiregulin (AREG), in the uterus during the estrus cycle using immunohistochemistry. The immunostaining for receptors and ligands of EGFR/ligand system was confined to membrane and cytoplasm of the target cells. Variations were observed, not only at the different stages of the estrous cycle, but also in the different tissue compartments of the uterus. However, it was detected that the immunostainings for NRG and AREG in the different cells do not show important differences at stages of the estrus cycle. In the luminal epithelium, strong immunostaining for ErbB1/HER1, ErbB2/HER2, ErbB4/HER4 and EGF was found at estrus. In the glandular epithelium, strong immunostaining for ErbB4/HER4 was observed at diestrus, while strong immunostaining for EGF was detected in both of estrus and diestrus. ErbB3/HER3 immunoreactivity in the stromal cells was higher at diestrus and anestrus, while ErbB4/HER4 immunoreactivity was lower at anestrus. In the myometrium, the highest levels of immunoreactivity of ErbB2/HER2 were found at estrus, while ErbB3/HER3 immunoreactivity was higher at anestrus. EGF immunoreactivity was lower at anestrus compared to other stage of cycle. Altered EGFR/ligand system expression during the estrus cycle suggests this growth factor system is a potent regulator of proliferation and differentiation events during preparation for implantation of bitch uterus.

Tissue distribution of some immune cells in bovine reproductive tract during follicular and luteal phase

More recent studies indicate that immune cells which secrete their secretory products or cytokines play an important role in reproductive system. In our study, immune cell populations (CD8+ T lymphocytes, CD68+ macrophages, plasma cells, siderophages, eosinophils) and expression of major histocompatibility complex (MHC) class I and class II were examined in female reproductive tract during follicular (n = 13) and luteal phase (n = 10). Plasma cells and eosinophil granulocytes are present in few numbers in luminal epithelium, but abundant in longitudinal muscle layer of uterus, whereas siderophages are the dominant cell type in stroma. Moreover, MHC‐I and ‐II+ cells are expressed by individual cells in organ layers, while CD8+ T cells and CD68+ macrophages are dominant in epithelium and muscle layer, respectively. In conclusion, we did not found significant changes in immune cells according to follicular and luteal phases, but localization and numbers in each organ have changed according to both organ and layers. These results indicate that these factors may play a crucial role not only to generate an immune response but also to have a role in regulation of physiological functions in female reproductive organs.

Functional characteristics of the growth factor receptor family and some ligands in the oropharyngeal cavity of the Chukar partridge (Alectoris chukar)

Abstract 1. The aim of the present study is to describe, immunohistochemically, the expression and cell type localisation of growth factor receptors and some of their ligands in the oropharyngeal organs of the Chukar partridge. 2. The tissue samples from 10 healthy adult partridges were dissected under ether anaesthesia and then embedded in paraffin following routine histological procedures. The immunoreaction for receptors and ligands of the epidermal growth factor receptor (EGFR)/ligand system was localised in the cell membrane, nucleus and cytoplasm of the luminal and glandular epithelial cells, stromal and striated muscle cells, and vascular endothelial and smooth muscle cells. 3. Variations were observed in the avian oropharyngeal organs. The immunostaining for the erbB1/HER1 (human epidermal growth factor receptor 1) and the EGF (epidermal growth factor) and AREG (Amphiregulin) ligands in the luminal epithelial cells was higher than in the glandular epithelial, stromal and striated muscle cells. However, the immunostaining for erbB3/HER3 (human epidermal growth factor receptor 3) and erbB4/HER4 (human epidermal growth factor receptor 4) were similar in the luminal epithelium, stromal and striated muscle cells. 4. Growth factor receptors and some of their ligands were localised in different cell types in the oropharyngeal organs. We suggest that erbB/HERs (human epidermal growth factor receptors) and their ligands play an important role in proliferation, differentiation, growth, survival and migration of the cells.