Transport of L-cystine in human umbilical vein endothelial cells in culture.

The uptake of L-cystine into cultured human umbilical vein endothelial cells has been shown to occur by a Na+-independent system which is inhibited by L-glutamate and L-homocysteine, but not by other amino acids. It is likely that the system transporting L-cystine is shared by L-glutamate. Thiol groups associated with membrane bound components appear to be essential for L-cystine uptake but it is not yet evident whether these constitute an integral part of the transporter per se.