Anotace:
The aim of this study was to evaluate the physiological effects of tylosin in rats. Tylosin was administered orally to pubertal male and female rats at concentrations of 0.005, 0.2, 10 and 200 mg/kg b.w. for 6 weeks. The overall body and organ weights were recorded. Serum levels of immunoglobulins, haematological values, histopathological lesions in different organs, and gene expression profiles in pituitary glands were investigated. The mean platelet volume was increased, and the monocyte count was decreased significantly in both male and female rats treated with tylosin. Compared to the untreated control, alanine transaminase in both types of rats and total serum bilirubin in female rats were increased significantly with the administration of tylosin (200 mg/kg), however, lactate dehydrogenase in female rats was decreased. The levels of immunoglobulin M were reduced in both male and female rats but immunoglobulin G levels were significantly reduced only in female rats which were treated with tylosin. Cell proliferation- and adhesion-associated genes were expressed more but apoptosis gene expressions were decreased in the pituitary gland of tylosin-treated rats. In conclusion, this study revealed that the use of tylosin at therapeutic dosage is possibly not completely safe.