EFFECTS OF CHRONIC ADMINISTRATION OF CYTIDINE-5'-DIPHOSPHATE CHOLINE (CDP CHOLINE) ON THE AGED FEMALE MOUSE HARDERIAN-GLAND

The effect of chronic intake of cytidine-5'-diphosphate choline (CDP c holine), a precursor of the membrane lipid phosphatidylcholine, was an alyzed in secretory cells of the Harderian gland (HG) of aged (26-mont h-old) female Swiss mice. These mice were treated with the drug from 1 2 months of age until they were 26 months old. The results obtained we re compared with those of an age-matched control group and another adu lt (12-month-old) control group. In both control groups, the HGs displ ayed secretory tubules formed by a single squamous epithelium of lipid -secreting cells. The tubule lumens were occupied by numerous small pl eomorphic porphyrin accretions. In contrast, the tubules of the CDP-ch oline-treated animals consisted of a single columnar epithelium, with lipid-secreting cells filled with lipid vacuoles. The most striking fe ature in the HGs of the CDP-choline group was the absence of porphyrin deposits. These observations indicate that porphyrin biosynthesis in female Swiss mice is maintained even in very old animals, and that chr onic administration of CDP choline prevents porphyrin deposition in th e HG of aged animals.