INTRACELLULAR PENETRATION OF MACROLIDES

Cell penetration: One of the main features of macrolides is their capa city to penetrate host cells. This properly is the basis of their acti on against intracellular microorganisms and can explain characteristic pharmacokinetics as well as interference with cell metabolism. Intrac ellular concentration: Erythromycin A derivatives with a single base g roup (roxithromycin) accumulate rapidly to a saturation point both in the cytoplasm and in granulations. Intracellular concentrations of der ivatives with two base groups do not reach saturation due to slow effl ux. Therapeutic action: Because of their intracellular concentration, macrolides are indicated for the treatment of cell-associated pathogen s. Exflux allows possible selective transfer into infected tissues. Ma crolides also have an effect on functional activity of the host cells.