Release of Alzheimer amyloid precursor derivatives stimulated by activation of muscarinic acetylcholine receptors.
Stimulation of m1 and m3 receptor subtypes with carbachol increased the basal release of APP derivatives within minutes of treatment, indicating that preexisting APP is released in response to receptor activation and protein kinases mediate neurotransmitter receptor-controlled APP processing.
Effect of inducing nocturnal serum melatonin concentrations in daytime on sleep, mood, body temperature, and performance.
- A. Dollins, I. Zhdanova, R. Wurtman, H. Lynch, M. Deng
- PsychologyProceedings of the National Academy of Sciences…
- 1 March 1994
The data indicate that orally administered melatonin can be a highly potent hypnotic agent and suggest that the physiological increase in serum melatonin levels, which occurs around 2100 h daily, may constitute a signal initiating normal sleep onset.
Brain serotonin content: physiological regulation by plasma neutral amino acids.
The main determinant of brain tryPTophan and serotonin concentrations does not appear to be plasma tryptophan alone, but the ratio of this amino acid to other plasma neutral amino acids that compete with it for uptake into the brain.
Brain Serotonin Content: Physiological Dependence on Plasma Tryptophan Levels
Brain serotonin cocentrations at 1 p.m. were significantly elevated 1 hour after rats received a dose of L-tryptophan and plasma and brain tryptophan levels were elevated 10 to 60 minutes after the injection, but they never exceeded the concentrationis that occur nocturnally in untreated aninmals as result of their normal 24-hour rhythms.
Sleep‐inducing effects of low doses of melatonin ingested in the evening
An animal model of antipsychotic-induced weight gain
Effects of exogenous melatonin on sleep: a meta-analysis.
Effects of normal meals rich in carbohydrates or proteins on plasma tryptophan and tyrosine ratios.
- R. Wurtman, J. Wurtman, M. Regan, J. McDermott, R. Tsay, J. Breu
- BiologyAmerican Journal of Clinical Nutrition
Whether carbohydrate-rich or protein-rich breakfasts, such as those Americans normally eat, produce substantial differences in the plasma tryptophan-LNAA ratio and in the corresponding ratio for tyrosine, the precursor of brain dopamine and norepinephrine is determined.
Precursor control of neurotransmitter synthesis.
This relationship allows precursor administration to produce selective physiologic effects by enhancing neurotransmitter release from some but not all of the neurons potentially capable of utilizing the precursor for this purpose, and allows the investigator to predict when administering the precursor might be useful for amplifying a physiologic process, or for treating a pathologic state.
The effects of low doses of caffeine on human performance and mood
Single doses of caffeine gave to 20 healthy male subjects assessed various aspects of performance and self-reported mood states, as well as plasma caffeine concentration, and found that as little as 32 mg significantly improved auditory vigilance and visual reaction time.