The effect of 5-fluorouracil on rat adrenal function.

This study was undertaken to determine the effects of 5-fluorouracil on corticosteroidogenesis and adrenal size in the rat. The rats were injected intraperitoneally with 5-FU (12.5 mg kg-1 or 25 mg kg-1), normal saline or actinomycin D (0.02 mg kg-1), daily for 10 days. High-dose 5-FU induces adrenal hyperplasia, in association with mild impairment of corticosteroidogenesis (manifest by lower corticosterone and higher ACTH levels). The response to low-dose 5-FU and actinomycin D is of lesser adrenal hyperplasia, relative to high-dose 5-FU (P less than 0.05) and elevated corticosterone levels. There may be a dose-related effect on the suppression of corticosteroidogenesis in the rat by 5-FU.