Fraser R, Dobbs B R, Rogers G W
Department of Pathology, Christchurch School of Medicine, New Zealand.
Hepatology. 1995 Mar;21(3):863-74.
The liver sieve, formed by the fenestrated hepatic sinusoidal endothelium, is a dynamic biofilter separating the hepatic blood from the plasma within the space of Disse. It filters macromolecules of differing sizes, especially lipoproteins. More specifically, it acts as a barrier to the large triglyceride-rich parent chylomicrons, while permitting the smaller triglyceride-depleted but cholesterol- and retinol-rich remnants to enter the space of Disse. There the remnants contact specific receptor sites on the hepatocyte microvilli. Thus, the liver sieve is the first site of hepatic selection and consequent metabolism of dietary cholesterol and fat-soluble vitamins, as well as rejection of dietary triglycerides. Therefore, perturbations of the porosity of the sieve, whether from changes in size, number of fenestrae, or composition of the underlying extracellular matrix within the space of Disse, will have a profound influence on the metabolism of lipoproteins. This disturbance of the homeostasis of lipids, including fat-soluble vitamins and cholesterol, as well as other macromolecules, may tilt the balance between health and disease in a variety of organs and tissues, such as the liver, kidney and arteries.
肝筛由有窗孔的肝血窦内皮形成，是一种动态生物滤器，将肝血与狄氏间隙内的血浆分隔开来。它能过滤不同大小的大分子，尤其是脂蛋白。更具体地说，它对富含甘油三酯的大的乳糜微粒起屏障作用，同时允许较小的、甘油三酯减少但富含胆固醇和视黄醇的残余物进入狄氏间隙。在那里，残余物与肝细胞膜微绒毛上的特定受体位点接触。因此，肝筛是肝脏对膳食胆固醇和脂溶性维生素进行选择及后续代谢，以及排除膳食甘油三酯的首个部位。所以，筛孔的孔隙率发生扰动，无论是由于窗孔大小、数量的改变，还是狄氏间隙内潜在细胞外基质组成的变化，都将对脂蛋白代谢产生深远影响。这种包括脂溶性维生素、胆固醇以及其他大分子在内的脂质稳态的紊乱，可能会在肝脏、肾脏和动脉等多种器官和组织中使健康与疾病之间的平衡发生倾斜。
