Cytogenetic effects of chloramphenicol in rats

Chromosomal aberration in bone marrow cells of albino rat (Rattus norvegicus) were taken as an indication of genotoxic action of chloramphenicol (CAP): Young adult male rats (Rattus norvegicus) received oral administration of 50 and 100 mg/kg of CAP. Samples of bone marrow cells were taken at 6, 12, 18, 24 and 30 hours post treatment. Pregnant female rats received a similar treatment at midterm and later stages of pregnancy in order to examine the genotoxic effects of CAP (50 mg/kg) on embryos through transplacental exposure. Chloramphenicol did not induce any effects after 50 mg/kg but chromosomal aberration were recorded at 100 mg/kg at 12 and 18 hours post treatment and 24 hours later the number of aberrent cells returned to control values in both young adult male and newborn pups of treated pregnant female rats.