Transport of antiviral agent 9-(S)-(2,3-dihydroxypropyl) adenine to animal cells.

Transport properties of 9-(S)-(2,3-dihydroxypropyl) adenine (DHPA) in cell cultures were studied. Transport of DHPA into chick embryo (CE), ZP (a cell line derived from rabbit lungs) and HeLa cells reached equilibrium values after 10 min incubation. The concentration of intracellular DHPA varied from 30 to 50 per cent of that in the medium. DHPA transport was only slightly affected during the lag phase of vaccinia virus replication. The opinion that DHPA is transported into the cell by facilitated diffusion, is supported 1) by the data on DHPA transport as a function of temperature and extracellular concentration, 2) by evidence of countertransport, 3) by temperature-dependent exit of DHPA, 4) by specific inhibition of DHPA transport in the presence of adenosine and deoxyadenosine and 5) by the fact that intracellular concentration of DHPA in equilibrium does not reach the concentration of DHPA in the medium. V and KM values varied in the range of 2-17 pmoles/min per 10(6) cells and 4-7 microM, respectively.