Abstract
An immunocompromised state to a slight degree was established in mice by the administration of 20-30 mg/kg of 5-Fluorouracil (5-Fu), an anticancer drug five times every other day. After 5-Fu administration, markedly observed were the decrease in the number of leukocytes, in the weight of spleen and thymus and the suppression of weight gain. these impairments gradually recovered to a normal level after discontinuation of 5-Fu administration. In order to determine the effect of retinoids on 5-Fu-induced immunosuppression, mice were fed with diet supplemented with 10 or 50 ppm of retinyl palmitate or retinoic acid. Retinoids showed a restoring effect on the number of leukocytes. In addition, a protective effect of retinoic acid diet was observed against infection with Listeria monocytogenes in mice given 5-Fu. However, there was no effect of the retinoids on weight loss or decrease in the weight of spleen and thymus caused by 5-Fu administration.
