Faculty Bibliography

Cortisol resistance to suppression by 0.5 mg of dexamethasone given at 11 p.m. was studied in 30 normal subjects, 17 to 78 years of age. Serum cortisol concentrations were determined by radioimmunoassay. A strong positive correlation was found between age and cortisol concentrations 9 hours after dexamethasone administration. The data suggest that aging, per se, might contribute to the increased cortisol resistance to suppression by dexamethasone reported in depression and dementia

The effect of a single dose (15 g/70 kg) of lecithin (95% phosphatidylcholine) on several measures of central cholinergic activity (memory, cortisol, prolactin, pulse, blood pressure) was assessed in individuals with Alzheimer's disease. In contrast to the reported effects of physostigmine, a cholinesterase inhibitor, lecithin had no effect on these parameters, despite significant increases in plasma and erythrocyte choline

During 6 weeks of lithium treatment, the RBC glycine and choline levels of five cognitively impaired geriatric subjects without affective disorders increased significantly and correlated with RBC and plasma lithium levels. The subjects' cognitive processes did not improve

Chronic treatment of rats with choline caused a decrease in the hypothermic response to pilocarpine. The action of choline on the muscarinic receptors is consistent with electrophysiological and binding studies, supporting a direct muscarinic action for choline. Administration of direct muscarinic agonists has been shown to cause a decrease in the number of muscarinic receptors. Thus, the long-term use of cholinergic precursors could have some adverse effects on central cholinergic functioning