Effect of three caffeine doses on plasma catecholamines and alertness during prolonged wakefulness

• Published in: European journal of clinical pharmacology Vol. 56; no. 8; pp. 537 - 544
• Main Authors: Kamimori, G.H., Penetar, D.M., Headley, D.B., Thorne, D.R., Otterstetter, R., Belenky, G.
• Format: Journal Article
• Language: English
• Published: Heidelberg Springer 01.11.2000; Berlin Springer Nature B.V
• Subjects: Adolescent; Adult; Biological and medical sciences; Body weight; Caffeine; Caffeine - blood; Caffeine - pharmacology; Catecholamines; Central Nervous System Stimulants - blood; Central Nervous System Stimulants - pharmacology; Clinical trials; Dose-Response Relationship, Drug; Double-Blind Method; Drug therapy; Epinephrine; Epinephrine - blood; High-performance liquid chromatography; Humans; Male; Medical sciences; Neuropharmacology; Norepinephrine; Norepinephrine - blood; Pharmacology. Drug treatments; Plasma; Psychoanaleptics: cns stimulant, antidepressant agent, nootropic agent, mood stabilizer..., (alzheimer disease); Psychology. Psychoanalysis. Psychiatry; Psychopharmacology; Reaction Time - drug effects; Reaction Time - physiology; Sleep; Sleep and wakefulness; Sleep Deprivation - blood; Sleep Deprivation - psychology; Wakefulness - drug effects; Wakefulness - physiology; Epinephrine; Human; Vigilance; Healthy subject; CNS stimulant; Psychotropic; Wakefulness; Norepinephrine; Catecholamine; Caffeine; Prolonged; Dose activity relation
• ISSN: 0031-6970; 1432-1041
• DOI: 10.1007/s002280000186

Determine the relationship between caffeine, catecholamines, and alertness during prolonged wakefulness. Following 49 h of prolonged wakefulness, each of 50 healthy males (18-32 years) orally ingested either a placebo or one of three doses of caffeine, 2.1 (low), 4.3 (medium), or 8.6 mg kg-1 body weight (high), in a randomized double-blind design. Wakefulness continued for an additional 12 h during which venous blood samples were collected for catecholamine and caffeine analysis [determined using high-performance liquid chromatography (HPLC)]. A sleep latency test, the Stanford sleepiness scale, and a choice reaction time test were administered periodically during the post-dosing period and served as measures of alertness (physiological, subjective, and behavioral, respectively). Caffeine had no significant effect on noradrenaline, but adrenaline was significantly increased between 1 h and 4 h post-dosing in the high dose group compared with a placebo group. Following caffeine administration, responses to sleep latency, sleepiness scores, and reaction time scores showed dose-related changes that were exhibited by significant correlation coefficients. The results indicate that high doses of caffeine have a significant and beneficial effect on alertness during prolonged wakefulness.