Gs. Bondy et al., GAVAGE ADMINISTRATION OF THE FUNGAL TOXIN FUMONISIN B-1 TO FEMALE SPRAGUE-DAWLEY RATS, Journal of toxicology and environmental health. Part A, 53(2), 1998, pp. 135-151
The fungal toxin fumonisin B-1 (FB1) is a contaminant of corn-based fo
ods and feeds produced by members of the genus Fusarium. Fumonisin B-1
toxicity was examined using gavage administration of purified toxin t
o female Sprague-Dawley rats. For 11 consecutive days each rat receive
d a single dose of FB, at the following concentrations: control (salin
e), 1, 5, 15, 35, or 75 mg FB1/kg body weight/d. Significantly depress
ed body weight and food consumption occurred at 35 and 75 mg FB1/kg/d.
By the end of the dosing period there were no significant changes in
food consumption. Kidneys and bone marrow were most sensitive to FB1 e
xposure. Changes in renal morphology were observed from 5 to 75 mg FB1
/kg/d, accompanied by transient changes in urine osmolality and urine
enzyme levels. increased cellular vacuolation was the primary change a
ssociated with bone-marrow toxicity, starting at doses of 5 mg FB1/kg/
d. Hepatotoxicity was indicated by reduced liver weight, elevated seru
m alanine amonitransferase (ALT), and mild histopathological changes o
ccurring at doses of 15 mg FB1/kg/d and higher. Increased cytoplasmic
vacuolation of adrenal cortex cells occurred in rats treated with 15 m
g FB1/kg/d and higher, indicating that the adrenals are also potential
targets of FB1. Elevated serum cholesterol, which is a consistent res
ponse to FB1, was observed at 5 mg FB1/kg/d and higher. Based on respo
nses in this study, gavage is an appropriate substitute for longer fee
ding studies. Compared to previous work with male rats, gender-related
differences in FB1 responses lacked consistency but indicated that ma
les may be marginally more sensitive than female Sprague-Dawley rats.