Selective appearance of Bunina bodies in amyotrophic lateral sclerosis. A study of the distribution in midbrain and sacral cord.

Bunina inclusion bodies were distribution abundantly in the nerve cell cytoplasm of case of amyothrophic lateral sclerosis (ALS). They appeared mainly in the motor nuclei of the brainstem and spinal cord on a routine examination. Although the oculomotor nucleus is known to be spared in ALS, Bunina bodies were found in 17% of the cells when examined in serial sections, much fewer than found in other motor of the brainstem. Bunina bodies were also found in 7.7% of the nerve cells of Onuf's nucleus in the ventral part of the anterior horn of the sacral cord, which has been thought to innnervate the striated of the vesicorectal sphincters and also to be spared in ALS. The number was less than in the lateral part of the anterior horn but the same as in the intermediolateral nucleus. This selective appearance of Bunina bodies in ALS may indicate that this inclusion is related to the primary functional disturbance in the motor neurons of ALS.