CEREBROSPINAL-FLUID EPINEPHRINE IN ALZHEIMERS-DISEASE AND NORMAL AGING

Central nervous system (CNS) adrenergic systems are involved in regula tion of behavior and blood pressure. The effects of Alzheimer's diseas e (AD) and normal aging on resting CNS adrenergic activity were estima ted by measuring cerebrospinal fluid (CSF) epinephrine (EPI) concentra tions in 74 persons with AD, 42 cognitively normal healthy older perso ns, and 54 healthy young persons. The responsiveness of CSF EPI to the alpha-2 adrenergic antagonist yohimbine and the alpha-2 adrenergic ag onist clonidine teas measured in smaller subject groups. Resting CSF E PI was higher in AD than in older or young subjects, and increased wit h dementia severity in AD subjects. There was Mo relationship between resting CSF EPI and blood pressure. CSF EPI increased following yohimb ine in AD and older subjects but not in young subjects. CSF EPI was un affected by clonidine in all subject groups. The agitation increase fo llowing yohimbine was substantially greater in AD subjects than in old er or young subjects. CNS adrenergic activity seems increased in AD, m ay further increase as AD progresses, and may be involved in the patho physiology of agitation. (C) 1998 American College of Neuropsychopharm acology. Published by Elsevier Science Inc.