Abstract
1. When 50 mg/kg of Methylnitrosourea was transplacentally inoculated to Donryu rats, 110 out of their 116 offsprings survived more than 163 days, and in 60 of these 110 were observed 93 tumors in total.2. The sites of the tumors were as follows : Two in the brain, 2 in the spinal cord, 16 in cranial nerves, 22 in spinal nerve root, 23 in peripheral nerves, and 28 in extraneural organs.Nerve tumors totally 61, accounting for 65.6% of the total, that was a majority.3. The nerve tumors histologically showed the picture of neurinoma or malignant neurinoma. Electron microscopical observation of some of these nerve tumor revealed that constituent cells contained axis cylinders and that the surface of the cell membrane was covered with basement membrane-like homogeneous substance. Thus they presented the traits of Schwann cells.4. Four tumors formed in the cerebrospinal substances histologically showed monotonous cell structure, and 2 of them presented the picture of oligodendroglioma and the other 2 that of ependymoma-like.5. Twenty four tumors, including 18 nerve tumors, were Subcutaneously transplanted into rats of the same strain. Twelve nerve tumors and 3 other tumors were transplacentable.6. Out of 28 tumors, formed outside the nervous system, 18 were found in the Kidney, 4 in the mammary gland, 2 in the peritoneal cavity, and 2 in the bone. The renal tumors grossly appeared to be cystic tumor, and presented a histological picture of nephroblastoma-like.7. Cerebellar hypoplasia and disorder in cerebellar cell structure were observed in many cases. In addition, dental dysplasia and cicatrization in renal parenchyma suggested the cytotoxic effect of MNU.8. Comparison between intravenous and transplacental MNU administrations revealed that in both cases cranial, spinal and peripheral nervous tissue were involved by tumors, but that there was difference in target organs of cancer in the viscera.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
