Acta Medica Okayama volume23 issue1

The hepatomas of the Donryu rats induced by feeding 4.dimethyl. aminoazobenzene for more than 191 days were transplanted into the brain of newborn rats of the same strain and the formed tumors were transplanted into the peritoneal cavity of adult rat of the same strain for the purpose to obtain transplantable strain of ascites hepatoma. As the result 4 lines of transplantable ascites hepatomas have been establised. The cells of these 4 hepatomas resembled their original liver tumor cells, respectively, showing the similar morphologic appearance to their mother cell. They showed less differentiated or more malignant characteristics in those taken from the tumor at the more advanced stages of DAB feeding. The liver tissues from the rat fed on DAB for 191 days had no tumor inducing activity when they were inoculated into the brains of the newborn rats (C 74). The liver tumors of the rats fed for more than 236 days produced the tumors in brain, which was serially transplantable (C 82), and kept the original morphologic pattern through serial transplantation and even in those growing in ascites. The tumor cells of the C 82 line showed the least malignancy among the 4 lines of ascites hepatoma established. Those of the C 83 line, which originated from the rat fed on DAB for 264 days, demonstrated the type of well.differentiated liver cell carcinoma with the trabecular arrangement of the tumor cells, but in ascites form they grew more rapidly than those of C 82. Those having most malignant characteristics were the cells of C 84.A which were derived from the rat fed on DAB for 312 days, and they were of the type of undifferentiated liver cell carcinoma. The island forming capacity of the C 84·A cells was the weakest among those of the 4 lines. C 84·B cells were also those derived from the same rat as that from which C 84.A originated and also showed the type of poorly differentiated liver cell carcinoma, but less malignant than those of C 84.A.

The disappearance of nucleolus has been traced in the rat erythroid cells in relation with the cell specialization under varying conditions, i. e. in anemia with or without treatment by bromouracil and aminopterin. To make the findings more reliable the observations have been made on tissue section as well as on the smeared samples as the nucleolus becomes often indistinct in smeared cell. The results indicate that under anemic condition nucleolus is lost by the late basoplilic stage. Treatment with bromouracil retained the nucleoli and cytoplasmic basophilicity till later stage of cell specialization suggesting some similar mechanism of RNA disintegration both in nucleolus and cytoplasm.

1. Dogs anesthetized with pentobarbital sodium were mainly used and effects of the distention of the small intestine on the movements of the gall bladder and the sphincter of Oddi were investigated. 2. The distention of the small intestine (jejunum or ileum) inhibited the rhythmic contraction of the gall bladder and duodenal movements, and relaxed the tone of the sphincter of Oddi, resulting in an increase of the outflow of fluid through the orifice of the common bile duct. 3. After cutting the bilateral thoracic splanchnic nerves together with extirpation of the bilateral upper lumbar sympathetic trunks, the inhibitory response on the movements of the gall bladder and the tone of the sphincter of Oddi was completely abolished. The vagus nerve did not take part in the reflex response described above. The transection of the spinal cord at the level between Thl and Th2 produced no change in the reflex responses. 4. Fwm the results described above it may be supposed that effects of the distention of the small intestine on the movements of the gall bladder and the sphincter of Oddi are produced via the thoracic and lumbar splanchnic nerves through the reflex center which is located in the spinal cord.

Adl2-induced tumors were homogenized and fractionated by the SCHNEIDER'S method. The CF test with the serum from tumor-bearing hamsters revealed the predominant presence of T-antigen in the mitochondrial and microsomal fractions. Hence, the rabbit was immunized with the microsomal fraction of tumors, and its serum was used to prepare the fluorescent antibody to T-antigen. The direct staining of the tumor cells with so prepared fluorescent antibody gave a staining pattern similar to the indirect staining with the serum of tumor-bearing hamsters. It thus appeares possible to stain T-antigen by the direct immunofluorescent method using the serum of rabbits hyperimmunized with the microsomal fraction of Ad12-induced tumors.

It is said blastformation can hardly be observed in the tissue culture of mouse lymphocytes. However, in our experiments of mouse lymphocytes (obtained either from axillary or cervical lymph nodes) mixed with various cells in combination of other cells as A+C3H, A+C57BL, or C3H+C57BL, it has been verified that these lymphocytes readily undergo blastformation in the presence of PHA (phytohemagglutinin M) as adjuvant. In the single tissue culture of these lymphocytes without PHA, the blastformation is observable in 6 per cent of the cells, while in the presence of PHA it is seen in 13. 7 per cent of the cells. In the cases of mixed cultures blastformation is observable in 14 per cent in the absence of PHA, whereas it is seen in 35.4 per cent in the presence of PHA. There is obviously a significant difference (p=O.OOI) in the blast. formation when cultured in the presence of PHA, and its reproducibility also proves to be quite high.

As the results of investigating the antigenicities of various fractions from the membrane systems of cancer cells, it has been found that the remarkable cancer-specific antigenicity exists in cancer cell mitochondria. With a particular reference to this antigenicity of cancer cell mitochondria, the antigenicities of the mitochondria of various kinds of rat ascites tumors and those of tumor-bearing rat liver mitochondria have been compared with those of normal rat liver mitochondria. In addition, it has been demonstrated that a strong tumor antitransplantability is induced when the recipient rat is immunized with the tumor cell mitochondria. In order to support these experimental facts, enzymatic activities of cancer cell mitochondria have been investigated also biochemically after treating the mitochondria with the antiserum to these mitochondria. 1. The most remarkable cancer specific antigenicity exists in mitochondria among the membrane systems of cancer cells. This cancer mitochondria-specific cancer antigenicity is common to all the ascites tumor mitochondria used here. 2. The original tissue- or organ-specific antigenicities diminish or disappear at the carcinogenic transformation of cells. 3. The tumor-bearing-organ specific antigenicity appears in the organs of animals bearing tumor. 4. The tumor antitransplantability is acquired when rats are immunized with these tumor cell mitochondria. 5. The inhibition of mitochondrial ATP·ase and respiratory activities is observed when the cancer cell mitochondria are treated with the anti. serum to the mitochondria.