The Effect of Caffeine on Ischemic Preconditioning
Summary
Ischaemic preconditioning (IP) describes the phenomenon that brief periods of ischaemia render the (myocardial) muscle more resistant to a subsequent more prolonged period of ischaemia and reperfusion. Animal studies have provided evidence that adenosine receptor stimulation is an important mediator of IP. As caffeine is an effective adenosine receptor antagonist already at concentrations reached after regular coffee consumption, we aimed to assess whether caffeine impairs IP in humans in vivo. We used a novel and well-validated model to study IP in humans: 99m-Tc-annexin A5 scintigraphy in forearm skeletal muscle. 24 healthy volunteers were randomly assigned to either caffeine (4 mg/kg/iv in 10 minutes) or saline before a protocol for IP.
Timeline
- Start
- 2003-09
- Primary completion
- —
- Completion
- 2006-01
Publications
- Background Rongen GA, Oyen WJ, Ramakers BP, Riksen NP, Boerman OC, Steinmetz N, Smits P. Annexin A5 scintigraphy of forearm as a novel in vivo model of skeletal muscle preconditioning in humans. Circulation. 2005 Jan 18;111(2):173-8. doi: 10.1161/01.CIR.0000151612.02223.F2. Epub 2004 Dec 27.
- Results Riksen NP, Zhou Z, Oyen WJ, Jaspers R, Ramakers BP, Brouwer RM, Boerman OC, Steinmetz N, Smits P, Rongen GA. Caffeine prevents protection in two human models of ischemic preconditioning. J Am Coll Cardiol. 2006 Aug 15;48(4):700-7. doi: 10.1016/j.jacc.2006.04.083. Epub 2006 Jul 24.
Drugs
| Evaluation | Drug | Modality | Dose | Route |
|---|---|---|---|---|
| Subject | Caffeine | Small molecule | 4 mg/kg | Intravenous |