|SOFT - TIAFT 1998||Poster Session 1||Wednesday October 7, 1998|
3H-COCAINE/BENZOYLECGONINE UPTAKE BY KERATINOCYTES AND MELANOCYTES IN CULTURE|
Patricia Emmerich, Gisela Skopp*, Lucia Pötsch
Institut für Rechtsmedizin, Johannes Gutenberg Universität Mainz, Am Pulverturm 3, 55131 Mainz, Germany
The accumulation of certain xenobiotics in pigmented tissues such as hair has already been reported, and melanin drug interaction has been suggested to be involved in the incorporation mechanisms of various drug substances during the biosynthesis of hair fibers.
In the present experimental approach the uptake of 3H-cocaine/benzoylecgonine (BZE) by keratinocytes was compared to that by melanocytes. The cultured cells were exposed to various 3H-cocaine/BZE concentrations and incubation periods up to 168 hours. All test series were run in triplicate.
In both cell types the uptake of 3H-cocaine/BZE was dependent on the drug concentration in the medium. After 72 hours an increased uptake of 3H-cocaine/BZE was already found, 3H-cocaine/BZE activity in 1 x 106 melanocytes was twice as much as in 1 x 106 keratinocytes. Following the time course over 168 hours, the uptake by melanocytes further increased leading to concentrations 5 times higher than in the keratinocytes.
These preliminary findings are discussed with respect to drug accumulation in the melanosomes due to melanin associated drug molecules.