Changes in spinal ganglia satellite and Schwann cells after aortic occlusion.

Ultrastructural ischemic changes of satellite and Schwann cells in lumbar spinal ganglia were studied in dog after single 80-minute and repeated 40-minute ligation of the abdominal aorta 3-48 hours survival. Satellite cells undergo greater changes than the Schwann cells. After a single ligation for eighty minutes, the satellite cell cytoplasm reveals lengthened or slightly vacuolated cisterns of the endoplasmic reticulum and more numerous lysosomes. The adneuronal surface of satellite cells shows retraction of the processes. Schwann cells, investing large myelinated axons contain markedly vacuolated endoplasmic reticulum and some osmiophilic inclusions. Three hours after repeated ligation the density of satellite cell cytoplasm is decreased and the cell processes of the adneuronal surface are less numerous. Some satellite cells containing large vacuoles undergo acute degeneration. Three hours after repeated ligation the Schwann cell cytoplasm reveals numerous lamellar bodies. Following 1-2 days survival after repeated ligation, strongly vacuolized satellite cells or those with lower cytoplasmic density are more frequent, but also hypertrophic satellite cells are visible. The changes of the Schwann cells are less advanced and manifest by the vacuolization of the organelles and the presence of lamellar bodies and other osmiophilic inclusions.