[Age-dependent DNA-content of brain, testis and ovar in men and rats (author's transl)].

The DNA-content of brain, testis and ovar of Wistar rats (inbred strain) was quantitatively analysed. We observed no significant differences between the several parts of the cerebrum, but between the cerebrum and the cerebellum. Furthermore we demonstrated alterations (with increase and decrease) of the DNA content of all brain parts as well as of testis and ovar during the course of life of this Wistar rat strain. These results and further investigations of the water content as well as of the absolute and of the relative weight of brains of these rats (in comparison to humans) extend the data and our knowledge about these subjects. It is possible to differentiate growth phases (by means of the DNA assays, which correlate with the morphologically well defined growth phases. Finally these results are fundamentals and presuppositions for investigations of the production metabolism of these organs because the DNA content is a better parameter (reference or relation figure, resp.) than the dry or wet weights and the protein or the nitrogen contents.