Transcellular transport of fluorescein dextran through an arterial endothelial cell monolayer.

Transcellular transport of fluorescein dextran (FD) of various molecular weights (4K, 10K, 20K, 70K and 150K daltons) through porcine arterial endothelial cells cultured on a type I collagen gel supported by a dacron sheet was studied and compared with the transport of low density lipoprotein labeled with rhodamine B (RB-LDL) described previously (Hashida et al., Cell Struct. Funct. 11, 31-42, 1986). The rate of FD transport through the monolayer depended on the size of the FD. FD transport was not temperature-dependent and was not a saturable process. Our findings show that FD transport differs from RB-LDL transport which is temperature- and dose-dependent. The mechanism of the transport of FD is compared with that of RB-LDL.

Transcellular transport of lipoprotein through arterial endothelial cells in monolayer culture.

To study the mechanism of lipoprotein transport through arterial endothelial cells, porcine endothelial cells were cultured on gelated type I collagen supported by a dacron sheet, and the transport of low density lipoprotein (LDL) labeled with rhodamine B isothiocyanate (RB-LDL) through the cells was measured. Light and scanning electron microscopy showed that the cells on the gel were confluent. There was little RB-LDL transport through the endothelial monolayer at 0 degrees C. RB-LDL transport through the monolayer at 37 degrees C was dose-dependent saturable at 0.4 mg protein/ml. The transport was energy-dependent, since its rate was affected by temperature and was inhibited by a combination of 2-deoxyglucose (50 mM) and NaN3 (10 mM). RB-LDL was shown not to be degraded during transport.