A comparative study of ofloxacin and ciprofloxacin erythrocyte distribution

• Published in: Biopharmaceutics & drug disposition Vol. 19; no. 2; pp. 71 - 77
• Main Authors: Colino, C. I., García Turiño, A., Sanchez Navarro, A., Lanao, J. M.
• Format: Journal Article
• Language: English
• Published: New York John Wiley & Sons, Ltd 01.03.1998; Wiley
• Subjects: Animals; Anti-Infective Agents - administration & dosage; Anti-Infective Agents - pharmacokinetics; Antibacterial agents; Antibiotics. Antiinfectious agents. Antiparasitic agents; Biological and medical sciences; ciprofloxacin; Ciprofloxacin - administration & dosage; Ciprofloxacin - blood; Ciprofloxacin - pharmacokinetics; Data Interpretation, Statistical; Dose-Response Relationship, Drug; erythrocyte distribution; Erythrocytes - cytology; Erythrocytes - drug effects; Erythrocytes - metabolism; Male; Medical sciences; ofloxacin; Ofloxacin - administration & dosage; Ofloxacin - blood; Ofloxacin - pharmacokinetics; pharmacokinetics; Pharmacology. Drug treatments; Rabbits; Intravenous administration; Red blood cell; Rabbit; Partition coefficient; Lagomorpha; Ofloxacin; In vitro; Blood plasma; Whole blood; In vivo; Vertebrata; Antibiotic; Fluoroquinolone derivatives; Mammalia; Animal; Distribution; Antibacterial agent; Ciprofloxacin; Pharmacokinetics; Comparative study; Quinolone derivatives
• ISSN: 0142-2782; 1099-081X
• DOI: 10.1002/(SICI)1099-081X(199803)19:2<71::AID-BDD72>3.0.CO;2-G

The present work deals with the in vitro and in vivo distribution of ofloxacin and ciprofloxacin in erythrocytes. In vitro studies were carried out in standard solutions prepared using fresh blood for a concentration range between 100 and 0.25 μg mL−1. A 5 mg kg−1 bolus dose was administered to rabbits and erythrocyte and plasma kinetics were determined over 8 h. A linear model was used to establish the relationship between plasma and erythrocyte concentrations of both quinolones in vitro. The mean partition coefficient values obtained were 1.04±0.02 and 1.32±0.03 for ofloxacin and ciprofloxacin, respectively. A decrease in the ciprofloxacin partition coefficient was observed at higher concentrations. Values ranged between 2.54±0.40 and 1.38±0.15 as the concentrations increased. The partition coefficients obtained from the linear relationship between plasma and erythrocyte concentrations established from the in vivo data were 0.80±0.58 for ofloxacin and 0.61±0.30 for ciprofloxacin. In vivo plasma and erythrocyte data analysis was performed by a deconvolution method and the theoretical transfer curves in erythrocytes were estimated. The distribution of both quinolones to erythrocytes is very rapid, probably due to a high permeability of erythrocyte membranes to these drugs. This was also confirmed by the parallelism between plasma and erythrocyte kinetics. © 1998 John Wiley & Sons, Ltd.