Abstract
1. Nerve cell perikaryon was isolated from rat cereberal cortex in bulk.
2. The size of the nerve cell perikaryon was small and contained 126μμg. of protein, 14μμg. of RNA and 6μμg. of DNA per cell.
3. Intraperitoneally administered labelled amino acids was incorporated into the protein of nerve cell perikaryon and the rate of incor-poration was higher than that of the protein of total cerebral cortex.
The authors are indebted to Prof. H, Koikegami for his advice in microscopical examination and to Prof. K. Ogata for his helpful discussions. This work was supported in part by a grant for Scientific Researches of the Ministry of Education.
