The Golgi apparatus of spinal ganglion neurons: quantitative changes with aging.

The Golgi apparatus of spinal ganglion neurons was studied in 1, 3.6, 6.7, and 8.8-year-old rabbits. The structure of this organelle did not differ in the four age groups examined. While the mean volume of the neuronal perikaryon increased progressively with age, the total volume of the Golgi apparatus remained stable throughout life. As a consequence, the mean percentage of perikaryal volume occupied by this organelle decreased significantly with age. Since the percentage of perikaryal volume occupied by lipofuscin remained at low levels throughout life, the ratio of the total volume of the Golgi apparatus to the functionally active volume of cytoplasm decreased with age. It is possible that this decrease is related to the reduction in neuronal metabolism that occurs in senescence. The age-related quantitative changes in the Golgi apparatus were very similar in large light and in small dark neurons. Finally, neither fragmentation, nor peripheral displacement of the Golgi apparatus was observed with advancing age.