Murano S, Shirai K, Saito Y, Yoshida S, Ohta Y, Tsuchida H, Yamamoto S, Asano G, Chen C H, Albers J J
Second Department of Internal Medicine, School of Medicine, Chiba University, Japan.
Scand J Clin Lab Invest. 1987 Dec;47(8):775-83.
A new lecithin:cholesterol acyltransferase (LCAT)-deficient family was found in Japan. In the proband, both LCAT activity and LCAT mass were deficient. The patient's parents, child, and sister, diagnosed as heterozygotes, had half-normal LCAT activity and LCAT mass. In the patient, an increase of intermediate-density lipoprotein (IDL, 1.006 less than d less than 1.019) fraction was observed. In postheparin plasma, both lipoprotein lipase and hepatic triglyceride lipase activities were low. Hydrolysis of [14C] triolein by human hepatic triglyceride lipase in patient IDL was decreased compared to that in IDL from normal postprandial serum. Preincubation of these IDL with normal plasma in the absence of 5,5'-dithiobis-(2-nitrobenzoic acid) (DTNB) increased the rate of hydrolysis, in the presence of DTNB, this increment was not observed. These results suggest that one cause of IDL increase in the LCAT-deficient patient might be the difficulty of hydrolysis of these lipoprotein particles by hepatic triglyceride lipase.
在日本发现了一个新的卵磷脂胆固醇酰基转移酶（LCAT）缺乏家族。在该先证者中，LCAT活性和LCAT质量均缺乏。患者的父母、孩子和妹妹被诊断为杂合子，其LCAT活性和LCAT质量为正常水平的一半。在该患者中，观察到中密度脂蛋白（IDL，1.006＜d＜1.019）部分增加。在肝素后血浆中，脂蛋白脂肪酶和肝甘油三酯脂肪酶活性均较低。与正常餐后血清的IDL相比，患者IDL中人类肝甘油三酯脂肪酶对[14C]三油酸甘油酯的水解减少。在不存在5,5'-二硫代双（2-硝基苯甲酸）（DTNB）的情况下，将这些IDL与正常血浆预孵育可提高水解速率，而在存在DTNB的情况下，则未观察到这种增加。这些结果表明，LCAT缺乏患者中IDL增加的一个原因可能是肝甘油三酯脂肪酶对这些脂蛋白颗粒的水解困难。
