Chromatolysis of A-cells of dorsal root ganglia is a primary structural event in acute acrylamide intoxication.

J Neurocytol 31(1):73-8 (2002) PMID 12652089

To test the hypothesis that a somatofugal wave of atrophy moving distally in the axon of primary sensory neurons leads to loss of myelinated nerve fibers in acrylamide neuropathy, rats (N = 18) were intoxicated with an initial dose of 75 mg acrylamide per kg body weight followed by daily treatment with 30 mg/kg for three, six and 12 days. Ten age matched saline treated rats served as controls. Numbers and mean volumes of A- and B-cell perikarya of the L5 dorsal root ganglion, numbers of myelinated axons and the mean cross sectional myelinated axon area 3 and 18 mm from the ganglion in the dorsal root and in the sural nerve were estimated using stereological techniques. After three days no changes in the number or size of primary sensory perikarya or myelinated axons were observed. However, after six days 11% of the A-cell perikarya showed signs of chromatolysis (P 0.001). After 12 days the rats showed signs of ataxia and 23% (P 0.001) of A-cell perikarya were chromatolytic. There was a tendency for atrophy of the mean perikaryal volume of A-cells (2P = 0.059). The size-frequency distributions of axonal area of myelinated fibers in the dorsal root 3 mm from the ganglion were displaced to the left towards smaller sizes (25-50% quartile: 2P 0.005 and 75-100% quartile: 2P 0.05). In conclusion, the primary structural event in acute acrylamide intoxication is chromatolysis of A-cells of the dorsal root ganglion without the occurrence of somatofugal axonal atrophy.