Morphological and cytochemical identification of the Golgi apparatus.

1. A modification of Elftman's direct silver method reveals both the lipochondria of Baker and the network of Golgi in the same cell. For purpose of distinction, it is proposed to call Baker's lipochondria the nucleopetal fraction, the Golgi network the nucleofugal fraction of the Golgi apparatus. 2. The nucleopetal fraction is located closer to the nucleus. It is spherical in shape and appears black in color. The nucleofugal fraction is located farther away from the nucleus. It is reticular in form and appears brown in color after silver impregnation by the modified Elftman's method. 3. These two fractions are separate entities. The network of Golgi is not due to deposition of silver on lipochondria. Lipochondria do not represent Golgi apparatus in living cells. 4. Aldehydes facilitate the demonstration of the nucleofugal fraction. Based on the circumstantial evidence presented, it appears that aldehyde dehydrogenase composed of a specific protein bound to a prosthetic group of flavin-adenine dinucleotide may be concentrated in this fraction. 5. Aldehyde dehydrogenase also functions as xanthine oxidase. It is suggested as a working hypothesis that under physiological condition, one of the functions of the nucleofugal fraction (Golgi network) is concerned with purine metabolism of nucleoproteins.