Fidge N H, Nestel P J, Suzuki N
Biochim Biophys Acta. 1983 Aug 29;753(1):14-21. doi: 10.1016/0005-2760(83)90092-9.
In this study we have compared the binding and degradation of human high density lipoprotein (HDL3), devoid of apolipoprotein E, by rat intestinal (mucosal) and adrenal cells and by human fibroblasts in culture. Binding of HDL3 to adrenal and intestinal cells was characterised by saturable, specific processes whereas skin fibroblasts from normal humans did not convincingly demonstrate saturability and had a lower affinity and capacity compared with adrenal and intestinal cells. Post-receptor events also appeared to differ. Cells from the adrenal cortex and gut showed similar binding affinities for HDL3 but the capacity for binding and for degrading HDL3 was much higher with intestinal cells. The large amounts of HDL degraded by intestinal cells suggest a specific role for the gut in HDL catabolism, and that, in the rat, intestinal cholesterol may be derived from circulating HDL. Finally, it is suggested that rat adrenal cortical and intestinal mucosal cells possess surface receptors for HDL3 which differ from the LDL receptor.
在本研究中，我们比较了大鼠肠道（黏膜）细胞、肾上腺细胞以及培养的人成纤维细胞对不含载脂蛋白E的人高密度脂蛋白（HDL3）的结合与降解情况。HDL3与肾上腺细胞和肠道细胞的结合具有可饱和的特异性过程，而正常人的皮肤成纤维细胞并未令人信服地表现出可饱和性，且与肾上腺细胞和肠道细胞相比，其亲和力和结合能力较低。受体后事件似乎也有所不同。肾上腺皮质细胞和肠道细胞对HDL3的结合亲和力相似，但肠道细胞结合和降解HDL3的能力要高得多。肠道细胞降解大量HDL表明肠道在HDL分解代谢中具有特定作用，并且在大鼠中，肠道胆固醇可能来源于循环中的HDL。最后，提示大鼠肾上腺皮质细胞和肠道黏膜细胞拥有与低密度脂蛋白（LDL）受体不同的HDL3表面受体。
