On Monday, scientists announced the discovery of a totally new type of blood vessel in our bones.
As detailed in a paper published in Nature Metabolism , the newly-identified vessels cross the surface of bones to their interior. Bones are organs, too, after all, and have a system for blood circulation not unlike our squishier organs.
The researchers dubbed the new vessels “trans-cortical vessels,” or TCV, because in mice they cross the entire hard outer shell of bone known as corticalis.
“It is really unexpected being able to find a new and central anatomical structure that has not been described in any textbook in the 21st century,” study co-author Matthias Gunzer, a professor at the University of Duisburg-Essen in Germany, said in a statement.
The scientists first found evidence of TCVs in mice long bones, they report in their study. Previously, scientists had only identified a handful of blood vessels entering and exiting mice bones. In mice, TCVs account for the majority of blood flowing through long bones, the study said.
The researchers also found evidence of similar TCV-like structures—although thicker than in mice—in small parts of human limb bones.
According to the study authors, the discovery of the vessels is a “missing link in the search for a fully functional closed circulatory system” that explains how blood flows in and out of bones.
Humans have looked inwards to unlock the many mysteries of our own bodies for millennia, but our anatomy still has its secrets.
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