Preferencje help
Widoczny [Schowaj] Abstrakt
Liczba wyników

Znaleziono wyników: 19

Liczba wyników na stronie
Pierwsza strona wyników Pięć stron wyników wstecz Poprzednia strona wyników Strona / 1 Następna strona wyników Pięć stron wyników wprzód Ostatnia strona wyników

Wyniki wyszukiwania

help Sortuj według:

help Ogranicz wyniki do:
Pierwsza strona wyników Pięć stron wyników wstecz Poprzednia strona wyników Strona / 1 Następna strona wyników Pięć stron wyników wprzód Ostatnia strona wyników
The umbilical cord is extremely important for correct fetal development. Just after the porcine umbilical vessels are diversified into arteries and veins, the direct transport of oxygen and nutrients between mother and fetus is possible. The aim of the present study was to determine the histological changes of developing porcine umbilical cord structures on day 40, 60, 75, 90 of pregnancy and after natural delivery by light microscopic observations. In the succeeding analyzed days of pregnancy the authors have observed changes of the umbilical vessels’ size, especially the enlargement of the muscular layer and increase in the size of the lumen. Furthermore, marked transmogrifications were noted in the amniotic and allantoic duct epithelium. The morphological reorganization of umbilical cord elements was relevant with increased concentration of elastic fibres stabilizing umbilical vessels, allantoic duct and amniotic epithelium in mucous connective tissue (Wharton’s jelly). These findings indicate that structural changes observed in the architecture of the porcine umbilical cord seem to be reasonable considering dynamic fetal growth.
The purpose of the present study was to determine the immunoreactivity of vascular endothelial growth factor (VEGF) and its two receptors: VEGFR-1 (flt-1, fms-like tyrosine kinase) and VEGFR-2 (flk-1, fetal liver kinase) on the endothelial cells of the lymphatic vessels in the area of the vascular subovarian plexus (VSP) of the broad ligament during different phases of the estrous cycle in pigs. The authors also investigated the expression and correlation between investigated factors and phases of the estrous cycle. The highest immunoreactivity for VEGF-A was observed in the lymphatic vessels of VSP at the follicular and early luteal phases of the estrous cycle. VEGFR-1 displayed the same pattern of immunostaining intensity as VEGF-A and VEGFR-2 revealed the highest immunoreactivity in the early luteal and late luteal phases of the estrous cycle. Additionally, VEGF-A, VEGFR-1 and VEGFR-2 expression was assessed by semi-quantitative Western Blot analysis, which revealed significantly higher levels of VEGF-A and VEGFR-2 proteins during the early-luteal and the follicular phase of the estrous cycle (P ≤ 0.001) and a very weak expression of VEGFR-1 during the whole estrous cycle. All factors displayed phase-related differences in the immunostaining intensity of the endothelial cells of the lymphatic vessels (VSP) in the porcine broad ligament of the uterus, suggesting that they are hormone-dependent during the estrous cycle in pigs.
The uterine artery and its branches are the most important vessels that supply the uterus with blood, nutrients and active substances. Epidermal growth factor (EGF) and its receptor (EGFR) are expressed in many tissues, including reproductive organs, and is involved in angiogenesis, embryo implantation and development as well as in proliferation and differentiation of various cells. The aim of our study was to determine EGF and EGFR immunoexpression in the uterine artery and its branches during the estrous cycle in the pig. The experiment was performed on cryostat sections of the uterine artery and its branches stained immunohistochemically by ABC method. Light microscopic observations revealed the phase-related immunoreactivity of EGF and EGFR in the endothelial cells of the uterine artery and its branches. The highest intensity of EGF and EGFR immunoreaction in endothelial cells of the uterine artery was observed in the follicular phase. A significant decrease in the intensity of EGF and EGFR immunoreactivity was found in the middle luteal phase. Similar results of the immunostaining were found with regard to EGFR. In the endothelium of the uterine arterial branches, a significant increase in the intensity of EGF and EGFR-immunoreac- tivity was observed in the middle luteal phase. A decrease in the intensity of EGF immunostaining was observed in the late luteal phase. The phase-related expression of EGF and EGFR in the endothelium of the uterine artery and its branches suggest the modulatory effect of EGF and its receptor on the uterine artery and the region supplying these vessels.
Localization and morphological features of lymphatic vessels leaving tissues of uterine horns and running through the broad ligament area were studied in mature cows after filling the lumen of the each lymphangion with varicoloured masses, mainly Microfil. The study has revealed that each branch of the lymphatic vessels emerged from both sides of the uterus and then formed double-layered networks, dorsal and ventral in the area of the mesometrium. The lymphatic branches under the uterus are very numerous and consist of enlarged precollector lymphangions. At the level of the ovary, the branches of vessels in both layers interweave each other forming the common pathway suggesting that lymph leaving the bovine uterus can be mixed in branches which are formed by elongated lymphangions running to lymphatic nodes.
Pierwsza strona wyników Pięć stron wyników wstecz Poprzednia strona wyników Strona / 1 Następna strona wyników Pięć stron wyników wprzód Ostatnia strona wyników
JavaScript jest wyłączony w Twojej przeglądarce internetowej. Włącz go, a następnie odśwież stronę, aby móc w pełni z niej korzystać.