Fall 2019 – Developing the Chick Chorioallantoic Membrane (CAM) Model to Detect Subtle Changes in Microvascular Structure with Low Doses of Sodium Fluoride

High-dose administration of sodium fluoride (NaF) induces hypertension in vivo. Both blood pressure and flow are extremely sensitive to subtle changes in microvascular radii. Low doses of NaF affect the response of endothelial cells to shear stress in vitro, which is a potent stimulus of microvessel growth in response to elevated blood flow. The chick chorioallantoic membrane (CAM) model has the unique property that the dramatic increase in flow during development can be measured in each microvessel of a specimen over successive days. Therefore, the purpose of the current study is to test the feasibility of using the chick chorioallantoic membrane (CAM) model to test the hypothesis that low-dose NaF limits microvessel growth. We have found that this novel use of the CAM model imposes additional requirements, including microvascular mapping, ex ovo culture technique, aseptic procedures and brightfield intravital microscopy. These requirements are necessary for concurrent repeated measurement of radius and blood flow velocity over successive days. Utilizing aseptic technique, during both incubation and intravital microscopy, is needed to prevent infection. These specific modifications of the standard CAM model not only make it possible to detect subtle changes in response to NaF, but also make the CAM model a novel platform for detecting the effects of very low doses of other potential teratogens