A stereological study of dorsal root ganglion cells and nerve root fibers from rats treated with inorganic mercury.

Unbiased stereological methods have been used to quantify the effects of inorganic mercury on the morphology of the fifth lumbar dorsal root ganglion cells and nerve root fibers. Adult male Wistar rats were treated with intraperitoneal injections of mercuric chloride (0.15 mg daily) for 30 days. The total numbers and mean volumes of A- and B-cell perikarya were estimated using the optical fractionator and the vertical rotator techniques. The total numbers of myelinated axons in the ventral and the dorsal roots were estimated with the two-dimensional fractionator technique and the areas of axon and myelin were estimated using the two-dimensional nucleator technique. No differences were found for any parameters in experimental and control animals, indicating that inorganic mercury intoxication alters neither the numbers or sizes of dorsal root ganglion cells and nerve root fibers nor the amount of myelin associated with the nerve fibers.