Pineal gland in rats suffering from malignancy.

Studies of the pineal gland in rats suffering from fibrosarcomas induced by 9, 10-dimethyl-1, 2-benzanthracene have been carried out. The weight of the pineal gland in these animals did not differ from that in control animals. However, the cells and their nuclei in the pineal glands of tumour bearing animals were larger and contained more lipid than those in the pineal glands of control animals. The results indicate that there is increased metabolic activity in the pineal glands of tumour bearing animals.