Faculty Bibliography

The effects of the muscarinic agonist, arecoline, on the concentration of homovanillic acid (HVA) in the cerebrospinal fluid of patients with Alzheimer's disease (AD) and controls were examined. Patients and controls received intravenous infusions of arecoline and a lumbar puncture was performed four hours after the infusion began. Arecoline induced a significant increase in the concentration of HVA in cerebrospinal fluid of Alzheimer's disease patients (p < .01) but not in controls. The differential HVA response to a muscarinic agonist in Alzheimer's disease is suggestive of an alteration in muscarinic receptor response. This finding may have potential implications for the pathophysiology and treatment of Alzheimer's disease

The failure of cholinesterase inhibitors to produce noticeable improvement in about half of patients with Alzheimer's disease (AD) may result from heterogeneity of neurotransmitter abnormalities in this disorder. This study examined whether pretreatment postural blood pressure (BP) drop, which presumably reflects sympathetic response, differed in patients who were responders or nonresponders to the cholinesterase inhibitor, HP 029. Twenty-three AD patients completed a double-blind dose-finding phase of a clinical trial in which four doses of HP 029 and placebo were administered. Evaluation for efficacy occurred after 7 days of treatment at each dose. Of the 23 patients, 12 were classified as responders in the dose-ranging phase of the study. Nonresponders demonstrated significantly greater decreases in pretreatment systolic postural BPs when going from a supine to sitting position than did responders. The greater postural BP drop in nonresponders may identify a subgroup of AD patients that responds poorly to cholinesterase inhibitors

This study evaluated the equivalence of five forms of the Selective Reminding Test, a widely used measure of verbal learning, 45 normal young and 45 normal elderly subjects were randomly administered three of the five test forms on three separate sessions. The five forms generally correlated well with one another and were of comparable difficulty, suggesting adequate test equivalence. Four of the five forms were particularly well matched

Despite widespread use of antidepressants, major gaps remain in our knowledge of the effects of antidepressants on human performance. While most single-dose studies with normal subjects have suggested that the more sedating tricyclic antidepressants tend to produce impairment, the effects of antidepressant treatment in clinical populations have been less thoroughly examined, with both drug-induced impairment and improvement reported. This review suggests that factors such as age, diagnosis, drug plasma concentration, and length of treatment need to be explored to establish the effects of antidepressants on performance in clinical populations

The concentration of corticotropin-releasing factor-like immunoreactivity (CRF-LI) in the cerebrospinal fluid (CSF) of 15 probable Alzheimer's disease (AD) patients with mild to moderate dementia and 10 neurologically normal age-matched controls was examined. There were no significant alterations in the mean CSF CRF-LI concentration in AD compared to controls. However, in the AD group, CSF CRF-LI correlated significantly with the global neuropsychological impairment ratings, suggesting that greater cognitive impairment was associated with lower CSF CRF-LI concentrations. There was a significant reduction in the CSF concentration of homovanillic acid (HVA) and 5-hydroxyindoleacetic acid (5-HIAA) in the AD patients, and there was a positive correlation between the concentration of CRF-LI and 5-HIAA in CSF. This latter finding suggests that serotoninergic neuronal systems may interact with CRF-containing neurons

The authors studied CSF gamma-aminobutyric acid (GABA) in 14 Alzheimer patients and nine age-matched normal subjects. The five normal subjects who were wives of the demented patients had higher CSF GABA concentrations than the four normal subjects without demented spouses