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Published on: June 16, 2022
Evidence for the Primo Vascular System above the Epicardia of Rat Hearts
Ho-Sung Lee1, Jeong Yim Lee, Dae-In Kang
1Ki Primo Research Laboratory, Division of Electrical Engineering, KAIST Institute for Information Technology Convergence, Korea Advanced Institute of Science and Technology (KAIST), Daejeon 305-701, Republic of Korea ; Pharmacopuncture Medical Research Center, Korean Pharmacopuncture Institute, Seoul 157-200, Republic of Korea.
Abstract:
We for the first time reported evidence for the existence of a novel network, a PVS, abovethe epicardium of the rat heart. (1) We were consecutively able to visualize the PVs and the PNs above the epicardial spaces of five rats' hearts by using Cr-Hx spraying or injection. (2) Hematoxylin and eosin (H&E) and toluidine blue staining of the PVs and the PNs showed that they consisted of a basophilic matrix; specifically the PNs contained several mast cells, some of which were degranulating into pericardial space. Also, 4', 6-diamidino-2 phenylindole (DAPI) images of the PVs and the PNs showed that they contained various kinds of cells. (3) Transmission electron microscopic (TEM) longitudinal image of the PVs showed that the sinuses contained many granules with high-electron-density cores in parallel with putative endothelial cells. (4) TEM images of the PNs demonstrated that they consisted of lumen-containing cells surrounded by fibers and that they had mast cells that were degranulating toward the epicardium of the rat heart. The above data suggest that mast-cells-containing novel network exists above the epicardium of the rat heart.
