Ion exchange analysis of porphyrins in urine

Abstract

Intubation of ethylene dibromide (7.5-10 mg/100 g of body wt) into the stomach of nonfasted Wistar rats induces DNA synthesis and cell division in the liver. The peak of DNA synthesis, as measured by 3H-methyl thymidine incorporation, was attained at or shortly after 24 h. The mitotic waves measured with the aid of colchicine occurred at 24-30 h and 48-54 h after ethylene dibromide treatment. Approximately 16% of liver cells entered mitosis. The increase in DNA synthesis was confirmed by autoradiography. The stimulation of liver cell mitosis occurs in nonfasted animals without apparent cell necrosis. Ethylene dibromide appears to be an effective mitogen for liver under some experimental conditions. The possible relationship between the mitogenic effect at a low dosage range and necrosis at a higher range is discussed. [EDB is a fumigant that is widely used for soil and grain.].