Figure 2

Micro-CT virtual sections of two primo vascular tissue samples from rats. (A) A three-dimensional (3D) surface image (90°) of the primo vascular system (PVS) tissue shown in Fig. 1 (left) and its transverse segments (right) at the primo node (PN) (a2) and primo vessel (PV) (a1 and a3). Virtual 3D segments (thickness = 33 µm) at the levels of a1, a2, and a3 are shown at a 45° forward tilt. Note the vessel-like structures, particularly in a2 and a3.(B) Three-dimensional images (90°) of another PVS tissue sample (left) and its cut surface images at the levels of the PN (b1–b4) and PV (b5–b8) (see Supplementary Video 2). The right panel presents cross-sectional images of the PVS tissue at the levels marked by b1–b8. The insets (b2-1 andb8-1) show the squared areas of the images b2 and b8 in an enlarged form to illustrate the low-contrast circular areas (~10 µm) inside the PN and PV bundles (thread-like structures in Fig. 1). Note also the higher contrast (brighter) boundary of the bundles and the larger low-contrast areas (yellow arrows) inside the bundles. CT = computed tomography.