Brain stem serotonin-synthesizing neurons in Alzheimer's disease: a clinicopathological correlation.
The location and number of brain stem serotonin-synthesizing neurons were analyzed in 11 patients with Alzheimer's disease (AD) and 5 age-matched controls using immunohistochemical techniques. In addition, the number of neuritic plaques and neurofibrillary tangles in the cortex and brain stem raphe was evaluated, as was the number of Nissl-stained raphe neurons. AD patients could be classified into two groups based on their raphe pathology; patients with such pathology (AD+) and those without (AD-). The number of large raphe neurons correlated significantly with the number of serotonin-synthesizing neurons in control material, indicating that all large neurons were serotonergic. This relationship was not apparent in AD+ patients, in whom the number of serotonin-synthesizing neurons correlated with the number of neurofibrillary tangles in the raphe of these patients. This indicates that in AD+ patients the serotonin-synthesizing neurons were selectively affected. There was no correlation between raphe and cortical pathology or raphe pathology and patient sex, age, mini-mental score or depression score, even when such scores were weighted for the interval between testing and death. There was a trend for the raphe pathology to correlate with the age of onset and duration of dementia and the Blessed dementia score in AD+ patients. Most AD+ patients with severe raphe lesions had clinical dementia only, while AD- patients had additional clinical features. The raphe lesions were more dramatic in AD+ patients with a rapid progression of symptoms.
D000368:Aged; D000369:Aged, 80 and over; D000544:Alzheimer Disease / Q000378:metabolism* / Q000473:pathology / Q000523:psychology; D001933:Brain Stem / Q000166:cytology / Q000378:metabolism* / Q000473:pathology; D002540:Cerebral Cortex / Q000378:metabolism / Q000473:pathology; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D016874:Neurofibrillary Tangles / Q000473:pathology; D009474:Neurons / Q000378:metabolism*; D011569:Psychiatric Status Rating Scales; D011903:Raphe Nuclei / Q000378:metabolism / Q000473:pathology; D012701:Serotonin / Q000096:biosynthesis*; D013194:Staining and Labeling
D012701:Serotonin