Sjöstrand Nils O
Karolinska Institutet, Idungatan 2, 5 tr 113 45 Stockholm.
Sven Med Tidskr. 2007;11(1):17-51.
The paper deals with concepts concerning the structure and function of the liver. According to the Hippocratic Collections the liver had five lobes. This concept was adopted by Galen and also became the concept of the medival physicians and teachers of anatomy. Still in his Tabulae Anatomicae from 1538, Andreas Vesalius illustrated the liver with five lobes, but in his public anatomy at Bologna in 1540 and in his famous books Fabrica and Epitome, both published in 1543, he stated that no such lobes existed in the human liver. The old wiew was based on animal dissections; thus in e.g. dog, cat, rabbit, swine and monkeys the liver has five or four distinct lobes. As a matter of fact the crucial question is not why, in a culture forbidding opening and dissection of human bodies, the on animals based concept, that the liver was split into five lobes, could arise and be maintained. The intriguing question is why the human liver still was said to have five lobes for more than 200 years after human autopsies had started. It is likely that the lag was partly due to belief in the ancient authorities and partly due to the fact that human anatomies were rare and most of the practical anatomy was still performed an animals. The role of the liver in the "physiological" thinkings of Plato, Aristotle, Herophilus, Erisitratus and Galen is also briefly touched. It is concluded that, with respect to physiology, the most important of Vesalius' contributions concerning the liver was not that he deprived the the human liver of its five lobes, but that he concluded in the Fabrica and Epitome that Galens concept of the liver as the source of the veins was wrong; the heart was the source of both veins and arteries. This concept had earlier been advocated by Aristotle and the agreement of Vesalius became a step towards the replacement of Galens physiology with the physiology of circulation of the aristotelian and brilliant experimenter William Harvey. A younger concept concerning the liver, which is based on findings in animals, but hardly relevant to man is the concept of lobules. This goes back to an eminent pioneer work on the liver of pig by F Kiernan in 1833. In this species there are distinct lobules, which everyone is completely invested by connective tissue. In man and many other mammals, however, the connective tissue is sparse and the lobular investment incomplete. The plates of hepatocytes form a continuum and the lobular structure is not fixed by a matrix of connective tissue but by dynamic factors as the pressure differance between the hepatic veins and the portal veins. Yet, still today, the liver lobule, although not present in man, always is presented in textbooks as the morphological and physiological unit of the liver.
本文探讨了有关肝脏结构和功能的概念。根据《希波克拉底文集》，肝脏有五个叶。这一概念被盖伦采纳，也成为中世纪解剖学医生和教师的概念。1538年安德烈亚斯·维萨里在他的《解剖图谱》中仍将肝脏绘成有五个叶，但在1540年他在博洛尼亚的公开解剖以及1543年出版的著名著作《人体的构造》和《概要》中，他指出人类肝脏中不存在这样的叶。旧观点基于动物解剖；例如，在狗、猫、兔子、猪和猴子中，肝脏有五个或四个明显的叶。事实上，关键问题不是在一个禁止对人体进行切开和解剖的文化中，基于动物的肝脏被分为五个叶的概念为何会产生并得以维持。有趣的问题是，在人体解剖开始后的200多年里，为什么人类肝脏仍被说成有五个叶。这种滞后可能部分是由于对古代权威的信仰，部分是由于人体解剖很少，大多数实际解剖仍在动物身上进行。还简要提及了肝脏在柏拉图、亚里士多德、赫罗菲卢斯、埃拉西斯特拉图斯和盖伦的“生理学”思想中的作用。得出的结论是，就生理学而言，维萨里关于肝脏的最重要贡献不是他剥夺了人类肝脏的五个叶，而是他在《人体的构造》和《概要》中得出盖伦关于肝脏是静脉之源的概念是错误的；心脏才是静脉和动脉的源头。这一概念早些时候由亚里士多德提出，维萨里的认同成为用亚里士多德学派和杰出实验者威廉·哈维的血液循环生理学取代盖伦生理学的一步。一个基于动物研究结果、但与人类几乎无关的关于肝脏的较新的概念是小叶概念。这可以追溯到1833年F·基尔南关于猪肝的一项杰出的开创性研究。在这个物种中有明显的小叶，每个小叶都完全被结缔组织包裹。然而，在人类和许多其他哺乳动物中，结缔组织稀疏，小叶包裹不完整。肝细胞板形成一个连续体，小叶结构不是由结缔组织基质固定，而是由肝静脉和门静脉之间的压力差等动态因素固定。然而，直到今天，肝脏小叶虽然在人类中不存在，但在教科书中总是被作为肝脏的形态和生理单位呈现。
