Preliminary study on serum enzyme changes in Long Evans rats given parenteral ochratoxin A, aflatoxin B1 and their combination.

Long Evans rats of both sexes were each administered a total of 250 micrograms aflatoxin B1 (AFB1), ochratoxin-A (OCH-A) or 500 micrograms AFB1 + OCH-A (1:1 ratio) in corn oil over 5 equal daily intraperitoneal (IP) injections of 50 micrograms/rat/day. Control rats were given a total of 1.25 ml corn oil over 5 equal daily IP injections of 0.25 ml/rat. All rats were observed daily for clinical signs of toxicity. Twenty-four hr following the last injection all rats were weighed, killed, examined for gross pathologic lesions and blood samples collected for routine hematologic and serum chemistry evaluation. All rats gained weight over the treatment period. Though not significantly different among the treatment groups, weight gain was significantly greater for males (54.0 g) than females (33.8 g). Routine hematology showed no difference among treatment groups. Serum enzyme aspartate aminotransferase (AST = SGOT) activities were indicative of hepatoxicity. Lactate dehydrogenase (LDH) activity was significantly increased in the AFB1 and AFB1 + OCH-A treatment groups, signifying a possible interaction between these 2 mycotoxins. LDH isoenzyme fractionation studies would be helpful in delineating the organ system(s) involved and the possible diagnostic value of this interaction.