Caffeine Attenuates Early Post-Exercise Hypotension in Middle-Aged Subjects

• Published in: American journal of hypertension Vol. 19; no. 2; pp. 184 - 188
• Main Authors: Notarius, Catherine F., Morris, Beverley L., Floras, John S.
• Format: Journal Article
• Language: English
• Published: New York, NY Elsevier Inc 01-02-2006; Oxford University Press; Elsevier Science
• Subjects: adenosine; Arterial hypertension. Arterial hypotension; Biological and medical sciences; Biomarkers - blood; Blood and lymphatic vessels; Blood Pressure - drug effects; caffeine; Caffeine - administration & dosage; Caffeine - pharmacokinetics; Caffeine - therapeutic use; Cardiology. Vascular system; Central Nervous System Stimulants - administration & dosage; Central Nervous System Stimulants - pharmacokinetics; Central Nervous System Stimulants - therapeutic use; Clinical manifestations. Epidemiology. Investigative techniques. Etiology; Double-Blind Method; Epinephrine - blood; Exercise - physiology; Exercise Test - adverse effects; Female; Follow-Up Studies; Fundamental and applied biological sciences. Psychology; Heart Rate - drug effects; Hemodynamics. Rheology; Humans; Hypotension - blood; Hypotension - drug therapy; Hypotension - etiology; Infusions, Intravenous; Male; Medical sciences; Middle Aged; Norepinephrine - blood; Post-Exercise Hypotension; risk factors; Vertebrates: cardiovascular system; adenosine; caffeine; risk factors; Post-Exercise Hypotension; Physical exercise; Human; Hypertension; Purine nucleoside; Adenosine; CNS stimulant; Psychotropic; Cardiovascular disease; Respiratory analeptic; Risk factor; Xanthine derivatives; Caffeine
• ISSN: 0895-7061; 1879-1905; 1941-7225
• DOI: 10.1016/j.amjhyper.2005.07.022

Sustained hypotension after an acute dynamic exercise bout is due primarily to peripheral vasodilation. We tested the hypothesis that adenosine-mediated vasodilation contributes to hypotension after exercise, by determining the effect of blocking its actions with caffeine.
Fourteen healthy middle-aged subjects (mean age = 51 ± 3 years), cycled to peak effort on 2 study days, after a randomized double-blind intravenous infusion of caffeine (4 mg/kg) selective for adenosine receptor blockade, or vehicle. Both studies were performed after 72 h of caffeine abstinence.
Infusion achieved 52.0 ± 6.1 μmol/L caffeine in plasma. Significant reductions in mean and diastolic blood pressure (BP) were elicited by prior exercise on the vehicle day (from 93 ± 2 to 85 ± 2 mm Hg
v from 79 ± 2 to 73 ± 3 mm Hg, respectively; both
P < .05), but not after caffeine infusion. Systolic and mean BP, 10 min after exercise, were higher on the caffeine than on the vehicle day (by 9 ± 3 and 6 ± 2 mm Hg, respectively;
P < .05), as was heart rate (HR) (100 ± 5
v 93 ± 4 beats/min;
P < .05).
These data suggest that endogenous adenosine contributes to early hypotension after exercise in healthy middle-aged subjects and underscore the importance of caffeine abstinence if BP or HR immediately after exercise is used to infer cardiovascular risk.