Stein O, Stein Y
J Cell Biol. 1967 May;33(2):319-39. doi: 10.1083/jcb.33.2.319.
A time sequence study of intracellular movement of labeled lipid in the liver was carried out on fasted and ethanol-treated rats injected with either palmitate-(3)H or glycerol-(3)H by electron microscopic radioautography. The elimination of water-soluble lipid precursors during specimen preparation was checked and found to be complete. The labeled lipid product in the tissue was identified as mostly triglyceride. A dehydration procedure was adapted to minimize the loss of lipid during specimen preparation. At 2 min after injection, the earliest time interval studied, both precursors were found to have penetrated the liver cells, and the label was found over both rough and smooth elements of the endoplasmic reticulum, which is the site of glyceride esterification. From 5 min on, in fasted and especially in ethanol-treated rats, the label was seen also over lipid droplets 0.5-2.0 micro in diameter, which represent "storage lipid" (slowly turning over compartment). Mitochondria became labeled mostly at later time intervals after injection. From 10 min on, concentration of label was seen over the Golgi apparatus, containing small osmiophilic particles. Association of label with groups of particles in smooth-surfaced vesicles and vacuoles in and near the Golgi apparatus and in the vicinity of the sinusoidal border was seen, both after palmitate-(3)H and glycerol-(3)H. It is proposed that these particles represent lipoproteins which are formed in the endoplasmic reticulum, "processed" in the Golgi apparatus, and transported in vacuoles to the sinusoid surface to be discharged into the circulation.
通过电子显微镜放射自显影术，对禁食和经乙醇处理的大鼠进行了一项关于标记脂质在肝脏细胞内运动的时间序列研究。这些大鼠被注射了棕榈酸 -（3）H 或甘油 -（3）H。检查了标本制备过程中水溶性脂质前体的消除情况，发现消除完全。组织中的标记脂质产物被鉴定为主要是甘油三酯。采用了一种脱水程序，以尽量减少标本制备过程中脂质的损失。在注射后 2 分钟（研究的最早时间间隔），发现两种前体都已穿透肝细胞，并且在内质网的粗面和滑面部分都发现了标记，内质网是甘油酯酯化的部位。从 5 分钟开始，在禁食的大鼠中，特别是在经乙醇处理的大鼠中，在直径为 0.5 - 2.0 微米的脂滴上也发现了标记，这些脂滴代表“储存脂质”（周转缓慢的部分）。线粒体大多在注射后的较晚时间间隔被标记。从 10 分钟开始，在含有小嗜锇颗粒的高尔基体上可见标记物的聚集。在注射棕榈酸 -（3）H 和甘油 -（3）H 后，均可见标记物与高尔基体及其附近以及窦状边界附近的光滑表面小泡和液泡中的颗粒群相关联。有人提出，这些颗粒代表脂蛋白，它们在内质网中形成，在高尔基体中“加工”，并通过液泡运输到窦状表面，然后排入循环系统。
