The influence of in vitro and in vivo exposure to antibiotics on mitogen-induced proliferation of lymphoid cells in rainbow trout (Oncorhynchus mykiss).
The influence of five different antimicrobial drugs on mitogen-induced lymphoid cell proliferation in vitro and after oral administration of the drugs was studied in rainbow trout (Oncorhynchus mykiss). The drugs tested were: oxolinic acid, oxytetracycline, florfenicol and trimethoprim in combination with sulfadiazine in ratio 1:5. In the in vitro tests, trimethoprim:sulfadiazine increased the 3H-thymidine incorporation into the DNA of phytohaemagglutinin and lipopolysaccharide-stimulated lymphoid cells while all the other drugs tested interfered negatively with the incorporation in a dose dependent manner. In the experiment with oral drug administration, the fish were fed 10 days with a therapeutic dose of the drugs. After the drug treatment, lymphoid cells were isolated from the head kidney of the fish and tested for proliferating capacity. All drugs except trimethoprim+sulfadiazine, suppressed the mitogenic response of the head kidney cells. The suppression of the response was more severe in phytohaemagglutinin-stimulated than in lipopolysaccharide-stimulated cells indicating that the T-cells were more vulnerable to the toxic effects of the drugs than B-cells.
Lundén
T
T
Institute of Parasitology, Department of Biology, Abo Akademi University, BioCity, Finland. tlunden@abo.fi
Bylund
G
G
D000284:Administration, Oral; D000818:Animals; D000900:Anti-Bacterial Agents / Q000008:administration & dosage / Q000494:pharmacology*; D002455:Cell Division; D002478:Cells, Cultured; D008214:Lymphocytes / Q000187:drug effects* / Q000276:immunology*; D017686:Oncorhynchus mykiss / Q000276:immunology*
D000900:Anti-Bacterial Agents