Using the Isolated Rat Placenta to Assess Fetoplacental Hemodynamics.

K L Garner,J A Griffith,E E Kelley,E C Bowdridge,E Devallance,T R Nurkiewicz

doi:10.3389/ftox.2022.814071

Abstract

Placental health is critical to fetal growth and maternal health during gestation. However, investigating placental flow in an ex-vivo isolated system where inflow is independently controlled has yet to be developed in the rat. Here, we describe a novel technique, isolated perfused placenta technique that allows for analysis of placental pressure outflow pressure, placental flow in rats at gestational day 20. Using this method, we successfully perfused placentas from dams and were able to observe increases in outflow pressure and flow as the inflow pressure to the placenta was increased in a step wise fashion. This method will help to advance the functional analysis of placental flow and therefore placental resistance and efficiency.

Highlights

The rat has been long established as an ideal animal model to study both pregnancy and the fetoplacental interface due to its similarities with the human
Analysis Techniques and Preliminary Studies with Isolated Perfused Placenta: In Figure 5, raw data tracings are provided that establish our proficiency with this novel approach
Umbilical vein pressure is of greatest interest as it represents placental resistance, post-placental hemodynamic conditions, and blood flow rate returning to the fetus

Summary

Introduction

The rat has been long established as an ideal animal model to study both pregnancy and the fetoplacental interface due to its similarities with the human. Fetal and placental weights at or near birth are positively corelated and are often used as an indicator of the ability of the placenta to provide the appropriate amount of nutrients to the fetus (Fowden et al, 2009). A decrease in maternal blood flow or improper placental vascularization, lead to decreased placental transport of nutrients and oxygen exchange through flow-limited passive diffuse processes (Fowden et al, 2006). This may potentially contribute to smaller fetuses at term

Methods

Results

Conclusion