Consequence of aflatoxin B1 ingestion on the membrane-bound liver endoplasmic reticulum Ca2+-ATPase of protein-undernourished Fischer F344 rats

Ingestion of the mycotoxin Aflatoxin B₁ (AFB₁) by protein-undernourished Fischer F344 rats for twelve weeks resulted in significant (p<0.05) increases in the proliferation of liver cells, reduced body weight and increased microsomal Ca²⁺-ATPase activity. Cyt. P₄₅₀ content, -Glutamyl Transferase (GGT) and Glutathione Transferase (GST) activities were unaffected. The ingestion of AFB₁ by normal rats had no effect on all the parameters investigated. It appears that the microsomal Ca²⁺-pumping ATPase of Protein-Undernourished (PU) Fischer F344 rats is more sensitive to the mycotoxin AFB₁ than its counterpart in well-nourished rats. The use of PU rat as animal model for studies on AFB₁ toxicity, particularly the effect of AFB₁ on the regulation of intracellular calcium ion concentration (Ca²⁺]_i), is suggested.