Intracellular transport route of albumin in cultured aortic endothelial cells

Effects of colchicine on intracellular albumin transport in aortic endothelial cells have been shown as a reduction of the endocytic activity (Liu et al., 1993) and albumin transcytosis (Antohe et al., 1993). Since microtubules are possibly involved in the movement of vesicles, it is important to understand that microtubules are associated with albumin transport within cells. In our in vitro study, the organization of endocytic compartments were analyzed after internalization of fluorescent-labeled albumin in cultured porcine aortic endothelial cells. We found that microtubules were not only involved in a later step but also early step of endocytosis (containing internalization).