Ahrendt S A, Fox-Talbot M K, Kaufman H S, Lillemoe K D, Lipsett P A, Pitt H A
Department of Surgery, Johns Hopkins Medical Institutions, Baltimore, Maryland.
Ann Surg. 1994 Nov;220(5):635-43. doi: 10.1097/00000658-199411000-00006.
Cholesterol phospholipid vesicles play an important role in the nucleation of cholesterol in bile. Recent studies have identified an additional vesicle population in human bile. In this study, the role of these small vesicles as cholesterol carriers was examined.
Gallbladder bile was obtained from 60 patients at cholecystectomy. Large vesicles, small vesicles, lamellae, and mixed micelles were separated using gel filtration chromatography.
Small vesicles were present in bile from the majority of patients both with and without cholesterol gallstones, whereas the void volume vesicle fraction was found almost exclusively in bile from patients with cholesterol gallstones. Both large vesicular and small vesicular cholesterol increased as total bile cholesterol concentration increased; however, the cholesterol-phospholipid ratio in the large vesicle fraction from patients with cholesterol stones was significantly greater than the ratio in small vesicles (1.6 +/- 0.3 vs. 1.0 < or = 0.1, p < 0.05). Whole bile cholesterol crystal appearance time was correlated significantly with the percentage of cholesterol transported by large vesicles (r = 0.63, p < 0.001) but not with the percentage of cholesterol present in small vesicles. Finally, large vesicles isolated by gel filtration chromatography formed cholesterol crystals faster than small vesicles (5.3 +/- 2 vs. 17.4 +/- 4 days, p < 0.01).
These data suggest that a heterogenous population of vesicles is present in human gallbladder bile. As bile becomes saturated with cholesterol, it increasingly is solubilized by both small and large vesicles. The small vesicles have relatively less cholesterol and are more stable than the larger variety, from which cholesterol is most likely to precipitate.
胆固醇磷脂囊泡在胆汁中胆固醇的成核过程中起重要作用。最近的研究在人体胆汁中发现了另一类囊泡群体。在本研究中，对这些小囊泡作为胆固醇载体的作用进行了研究。
在胆囊切除术时从60例患者获取胆囊胆汁。使用凝胶过滤色谱法分离大囊泡、小囊泡、片层和混合微团。
大多数有或无胆固醇结石患者的胆汁中均存在小囊泡，而几乎仅在胆固醇结石患者的胆汁中发现空体积囊泡部分。随着胆汁总胆固醇浓度升高，大、小囊泡中的胆固醇均增加；然而，胆固醇结石患者大囊泡部分的胆固醇-磷脂比值显著高于小囊泡（1.6±0.3对1.0≤0.1，p<0.05）。全胆汁胆固醇晶体出现时间与大囊泡转运胆固醇的百分比显著相关（r=0.63，p<0.001），但与小囊泡中胆固醇的百分比无关。最后，通过凝胶过滤色谱法分离的大囊泡比小囊泡更快形成胆固醇晶体（5.3±2对17.4±4天，p<0.01）。
这些数据表明人体胆囊胆汁中存在异质性囊泡群体。随着胆汁胆固醇饱和，它越来越多地被大、小囊泡溶解。小囊泡胆固醇相对较少，比大囊泡更稳定，胆固醇最可能从大囊泡中析出。
