Caffeine impairs intramuscular energy balance in patients susceptible to malignant hyperthermia.

Abstract

Malignant hyperthermia (MH) is a metabolic myopathy with an abnormal release of calcium by the sarcoplasmic reticulum (SR), triggered by volatile anesthetics and succinylcholine. Similarly, caffeine enhances Ca(2+)release by the SR in vitro. In a prospective, randomized study, high-energy phosphates were studied by intramuscular 31-phosphorus magnetic resonance spectroscopy ((31)P-MRS) in 10 MH-susceptible (MHS) and 7 MH-nonsusceptible (MHN) subjects before and after injection of 0.5 ml caffeine (20 mM). Intramuscular energy balance, measured by the ratios of P(i)/PCr and P(i)/gamma-ATP, did not differ between MHS and MHN patients before and after intramuscular caffeine injection. However, within each group, P(i)/PCr and P(i)/gamma-ATP increased significantly only in the MHS group. Intramuscular caffeine injection seemed to impair the metabolic balance in MHS individuals. This may reflect a local calcium overload leading to consumption of high-energy phosphates and increase of inorganic phosphate. Intramuscular stimulation by caffeine and (31)P-MRS may provide a valuable tool to investigate MH-related metabolic disturbances.

• Authors: Zoran Textor, Meinrad Beer, Martin Anetseder, Herbert Köstler, Erwin Kagerbauer, Werner Kenn, Dietbert Hahn, Norbert Roewer
• Journal: Muscle & nerve (Muscle Nerve) Vol. 28 Issue 3 Pg. 353-8 (Sep 2003) ISSN: 0148-639X [Print] United States
• PMID: 12929196 (Publication Type: Clinical Trial, Journal Article, Randomized Controlled Trial, Research Support, Non-U.S. Gov't)

Chemical References

• Phosphorus Radioisotopes
• Phosphocreatine
• Phosphorus
• Caffeine
• Calcium

Topics

• Adult
• Age Factors
• Caffeine
• Calcium (metabolism)
• Calcium Signaling (drug effects, physiology)
• Disease Susceptibility (diagnostic imaging, metabolism, physiopathology)
• Female
• Humans
• Injections, Intramuscular
• Magnetic Resonance Spectroscopy
• Male
• Malignant Hyperthermia (diagnostic imaging, metabolism, physiopathology)
• Metabolic Diseases (diagnostic imaging, metabolism, physiopathology)
• Middle Aged
• Muscle, Skeletal (drug effects, metabolism, physiopathology)
• Muscular Diseases (diagnostic imaging, metabolism, physiopathology)
• Oxidative Phosphorylation (drug effects)
• Phosphocreatine (metabolism)
• Phosphorus (metabolism)
• Phosphorus Radioisotopes
• Prospective Studies
• Radionuclide Imaging
• Sex Factors