Observation of the Primo Vessel Approaching the Axillary Lymph Node with the Fluorescent Dye, DiI

Figure 3

A primo vessel in a lymph duct. (a) A piece of the lymph duct (broken line) was taken, fixed, and put on a slide glass. The primo vessel (arrow) was hardly identifiable. (b) The primo vessel (arrow) showed strong fluorescence due to the DiI. The lymph duct did not show fluorescence, which demonstrated that DiI was absorbed very weakly by the lymph duct.