Toxicologic and immunologic effects of sublethal doses of cyclopiazonic acid in rats.

Effects of cyclopiazonic acid (CPA) on humoral immunity, cell-mediated immunity, weight gain, organ weights, clinical chemical and hematologic values, and gross and microscopic lesions were evaluated. Four groups of rats, each containing 3 males and 3 females, were given 0, 0.1, 1, and 5 mg of CPA/kg of body weight intraperitoneally for 28 days. A dosage level of 5 mg/kg produced a significant (P less than 0.05) decrease in weight gain. Rats given 0.1 or 1 mg of CPA/kg had a significant (P less than 0.05) reduction in antibody titer against sheep RBC 5 days after injection. The 0.1 mg/kg group also had a significant reduction in antibody titer 7 days after injection. Microscopic lesions were limited to liver, and kidneys and were characterized by vacuolated to granular hepatocyte cytoplasm and dilated renal convoluted tubules, many having pyknotic nuclei and scattered hyaline casts.