Effect of partial hepatectomy on tumor incidence and metabolism of mice fed thioacetamide.

Six-week-old male Swiss mice were given 0.03% thioacetamide (TAA) in the diet 24, 72, and 168 hours after partial hepatectomy. TAA-treated mice from all three groups were killed when they were 4, 9, and 13 months old. Intact and partially hepatectomized animals on normal diets served as controls. None of the controls evidenced neoplasms at any age. All three experimental groups developed liver tumors earlier than did intact mice treated with the TAA diet. Progressive metabolic studies on the livers or tumor tissues of treated mice showed that the levels of glucose-6-phosphatase, fructose-1,6-diphosphatase, and glycogen decreased significantly in the 4-month-old treated group when there was no significant alteration in liver histology. These parameters were lowest in the tumor tissues of treated mice.

Arecoline tumorigenicity in Swiss strain mice on normal and vitamin B deficient diet.

Arecoline, a major alkaloid present in betel nut, was administered daily by gavage feeding to Swiss male and female mice at a dose of 1 mg/day/mouse five times a week, either alone or in combination with KNO3 or KNO3 + lime. Swiss mice of both sexes kept on a vitamin B complex-deficient diet were tested in a similar manner and compared with those receiving a normal diet. In the mice receiving a normal diet it was observed that arecoline induced tumors in 40% of males but failed to produce tumors in any of the females. Arecoline tumorigenicity in females was evident only when they received a vitamin B-deficient diet. Arecoline tumorigenicity was not evident in males when they were treated simultaneously with KNO3 + lime and kept on a normal diet. However, the same treatment administered to male mice kept on a vitamin B complex-deficient diet induced tumors in 39%.

Toxicological study of Semecarpus anacardium nut extract.

Toxicological study was carried out in rats with chloroform-soluble fraction of the nuts of Semecarpus anacardium to determine its safe non-toxic dose. The fraction produced toxicity at all levels tested (50-400 mg/kg) but the extent of toxicity was found dose-dependent. At lower doses this fraction induced partial growth inhibition over 36 days and higher doses proved fatal within 6 days. It was observed that 230 mg/kg caused 50% mortality in rats and this value is 1380 mg/m2 when expressed for body surface area. This work will be of some use in the cancer chemotherapy study of the fraction.

Protection by testosterone propionate against the nephrotoxicity of 2-aminoanthraquinone in Fischer rats.

The role of gonadal hormones in the nephrotoxicity of the hepatocarcinogen 2-aminoanthraquinone (2-AAQ) was investigated. Intact and castrated four week old Fischer rats of both sexes and castrated female rats with subcutaneous implants of testosterone propionate pellets were fed 2% 2-AAQ in a Wayne meal diet. After 12 weeks of ad libitum feeding the animals were then given control diet. Based on survival, body, liver and kidney weights, and the histopathological evaluation of the kidneys, castrated female rats given testosterone propionate were afforded the greatest protective effect against the nephrotoxicity of 2-AAQ.