Hamilton J A, Oppenheimer N J, Addleman R, Clouse A O, Cordes E H, Steiner P M, Glueck C J
Science. 1976 Dec 24;194(4272):1424-7. doi: 10.1126/science.188128.
High-field (63.4 kilogauss) Fourier transform nuclear magnetic resonance spectroscopy 13C in natural abundance has been used to study the structural organization and molecular dynamics of constituent lipids of normal human very low-density lipoproteins (VLDL) and low-density lipoproteins (LDL). The same method was used to study the abnormal beta-VLDL of two type III hyperlipoproteinemia patients having markedly differing ratios of VLDL cholesterol to triglyceride (0.3 and 0.6, respectively). Resolution obtained at 63.4 kilogauss has made possible the assignment of several additional resonances of cholesterol ring carbon atoms, not resolved in earlier studies at lower fields, in the VLDL spectra. The rotational reorientation of the ring portion of cholesteryl esters in VLDL (normal) and beta-VLDL (abnormal) is not highly anisotropic and is similar to that for cholesteryl esters disolved in excess triolein. The rotations of cholesteryl esters in LDL are more highly anisotropic and significantly more restricted. The results suggest that the structural organization of the lipid components in beta-VLDL resembles that found in normal VLDL but differs significantly from that for normal LDL.
利用高场（63.4千高斯）天然丰度的傅里叶变换核磁共振碳谱，研究了正常人极低密度脂蛋白（VLDL）和低密度脂蛋白（LDL）中组成脂质的结构组织和分子动力学。采用同样的方法研究了两名III型高脂蛋白血症患者的异常β-VLDL，其VLDL胆固醇与甘油三酯的比率明显不同（分别为0.3和0.6）。在63.4千高斯下获得的分辨率使得在VLDL光谱中能够归属几个胆固醇环碳原子的额外共振峰，这些峰在早期较低场强的研究中未得到分辨。VLDL（正常）和β-VLDL（异常）中胆固醇酯环部分的旋转重取向并非高度各向异性，与溶解在过量三油精中的胆固醇酯相似。LDL中胆固醇酯的旋转更具各向异性，且受到的限制明显更大。结果表明，β-VLDL中脂质成分的结构组织类似于正常VLDL，但与正常LDL有显著差异。
