Aluminum chloride induced neurofibrillary changes in the developing rabbit a chronic animal model.

Aluminum chloride injected into the brains of developing rabbits produced profound neurofibrillary changes to neurons of spinal cord and cerebrum similar to those produced in adult rabbits, along with a variety of clinical symptoms with the exception of seizures. Approximately half of the rabbits survived for more than three weeks, and many survived for several months. Many rabbits with large numbers of neurofibrillary changes had no clinical signs and symptoms. The dynamics and topography of the neurofibrillary changes induced by aluminum chloride are described over a period of several months. Many neurofibrillary tangles were seen in neurons of spinal cord and cerebrum up to 60 days after injection of aluminum chloride. There was no obvious correlation between the degree of neurofibrillary changes and the severity of the clinical signs and symptoms. Animals examined at 85 and 100 days after injection of aluminum chloride had fewer neurofibrillary tangles of none at all, and apparently they had recovered from the neurofibrillary changes. This chronic animal model will allow better investigations of the biochemistry and pathology of neurofibrillary changes, and it will enable behavioral studies to be performed in animals with neurofibrillary changes.