【Animal Experiment】-Using genetically modified mice combined with lineage tracing technology to decipher the new origin of coronary arteries

  The scientific community generally believes that the coronary arteries of human beings are derived from the coronary arteries formed in the womb, but this is only a hypothesis and has not been strictly demonstrated. Zhou Bin's research group used genetically modified mice combined with lineage tracing technology to study the origin and developmental mechanism of coronary arteries and found that the formation of coronary arteries is in order: the coronary arteries outside the ventricular wall are derived from the blood vessels generated in the early embryonic development; ventricular wall The inner coronary arteries are newly formed after birth. As a result, another "origin" of coronary arteries-the endocardium "surfaces".

  The study also found that coronary arteries come from two different "mother cells": the coronary arteries in the outer layer of the heart wall are mainly developed from subepicardial stem cells, while the coronary arteries in the inner layer of the heart wall are derived from endocardial stem cells. . These two types of "mother cells" are not only different in location, but also in the development time: the coronary arteries in the outer layer of the heart wall have begun to develop during the embryonic period, while the coronary arteries in the inner layer of the heart wall are 1 to 2 weeks after birth Just started to grow.

  Zhou Bin et al. also proposed for the first time that the origin of coronary arteries can be divided into two blood vessel groups, namely the first coronary artery group located outside the ventricular wall and the second coronary artery group inside the heart (including the inside of the ventricular wall and the interventricular septum). Quantitative analysis shows that the second coronary artery group from the endocardium is the "biggest contributor" to the supply of blood to the heart, because it is responsible for supplying about 60% of the myocardium in the heart.

  Experts believe that this major discovery provides important clues to the pathogenesis, diagnosis and treatment of congenital heart disease, such as myocardial insufficiency and congenital coronary fistula, and also provides important clues to the coronary arteries after myocardial infarction caused by coronary heart disease. Regenerative therapy and in vitro artificial heart angiogenesis studies have laid a theoretical foundation.