Building the lymphatic system using the amniotic membrane

Introduction and purpose: During long-term intravascular fluid infusion in sheep fetuses, there is a large increase in the production rate of the fetal lymphatic system, while the volume of amniotic fluid increases only slightly due to increased intramembranous absorption. The present study tested the hypothesis that the construction of the lymphatic system using the amniotic membrane occurs in the groin of Goshfand. Materials and methods: Chronically catheterized fetal sheep with a mean gestation of ۱۲۶ ± ۱ days (SE) were either injected intravenously with ۷ L of normal saline over ۳ days (۸ sheep) or as a time control (۶ sheep). Amniotic fluid volume and lymphatic system proliferation rate were measured daily. Daily intramembrane permeability was estimated equal to ۹۹ m of technetium injected intra-amniotic. The abundance of messenger RNA of growth factor, lymphatic system and vascular endothelium in amnion, chorion and placenta was determined using northern blot analysis. Statistical analyzes included analysis of variance. Results: In injected fetuses, amniotic fluid volume, lymph system production increased by ۸۹۱ ± ۱۴۴ ml and ۳۴۸۸ ± ۴۸۷ ml per day (P < ۰.۰۱) on the third day of infusion compared to no change over time in control fetuses. In injected embryos, the estimated membrane absorption increased by ۴۹۹ ± ۴۲۷۶ ml during the ۳-day infusion. The intramembrane permeability of technetium ۹۹ m was similar over time in the two groups. In the injected group, growth factor messenger RNA levels in vascular endothelial lymphatic system in amnion, chorion and placenta increased ۲-۴ times compared to the control group (P<۰.۰۰۱). Conclusion: The increased production of the lymphatic system may mediate the increased intramembrane absorption caused by volume loading diuresis. However, this does not occur by passive mechanisms. Wehypothesize that the growth of the lymphatic system mediates increased intramembrane uptake by increasing vesicular transport.

کلیدواژه ها:

Amniotic membrane ، lymphatic system transplant ، sheep groin