Control of Blood Vessel Identity: From Embryo to Adult

Abstract

History R ecognition of the differences between arteries and veins can be found in Huangdi nejing suwen (The Yellow Emperor's Manual of Corporeal Medicine). 1) This historical document described the ancient concept of two separate circulations of body fluids; blood, pumped by the heart and then continuously through the arteries, veins and capillaries, and Ch'i, an ethereal form of ener-gy. 1) Ishinpo, the oldest surviving Japanese medical text, was written by Yasuyori Tamba in 984, and describes ba-sic vascular anatomy and circulation. Kaitai-shinsho is the oldest and most famous Japanese anatomy text; it was written by Genpaku Sugita in 1774 and contains detailed anatomical figures of arteries and veins, with early evi-dence of influence by Western medicine on Japanese medicine. 2) Outside of Asia, the first known documentation of ba-sic circulation was in Greece, approximately 500 BC; Al-cmaeon of Croton, an early pioneer of animal dissection, observed arteries and veins to be distinctive structures. 3) Hippocrates (460–370 BC), considered the founder of Western medicine, was the first to propose that blood travels in a circle. Using human cadaver dissections, Herophilus of Chalcedon (300 BC) elaborated on the dis-tinction between arteries and veins and discovered that arteries contained blood rather than air. 3) Claudius Galenus of Pergamum (129–216 AC) elevated the earlier Hippocratic concepts to scientific levels through observation of animal dissection and experimen-tation. He confirmed that arteries contained blood and that arteries and veins were distinct, each with a different type of blood. Galen believed that nutritive blood was made by the liver and carried through veins to the organs where it was expended, and that vital blood was made by the heart and pumped through arteries to carry spirits. He claimed that blood flowed through the heart via in-terventricular septal pores and that arteries had innate pulsatility, rather than being pumped by the heart.