Brain choline acetyltransferase reduction in SIV infection. An index of early dementia?

HIV infection at late stages is associated with neurological complications including impaired motor and cognitive functions. We used simian immunodefi ciency (SIV)-infected rhesus monkeys, an animal model of HIV infection, to investigate changes in choline acetyltransferase (ChAT) activity, a biochem ical marker of cognitive function, in post-mortem brains during early, asym ptomatic SIV infection and AIDS. ChAT activity was dramatically reduced in putamen and hippocampus already during asymptomatic infection. In animals w ith AIDS, ChAT activity was further decreased. The reduction of ChAT was no t related to brain viral load or CNS pathological lesions. Our results demo nstrate deficits in ChAT activity already during the first months of SIV in fection and imply that cognitive dysfunction may occur early in immunodefic iency viral infections. NeuroReeort 11:2391-2393 (C) 2000 Lippincott Willia ms & Wilkins.