Adrenergic control of plasma magnesium in man.
Level 2 - randomized trial
Randomized placebo-controlled trial evaluating physiological infusions in healthy subjects
PubMed 3542342 · doi:10.1042/cs0720135
What was done
Eight healthy participants received intravenous infusions of L-adrenaline (achieving pathophysiological concentrations), salbutamol (a beta-2 agonist), and placebo in a controlled experimental design. Investigators measured serial changes in plasma magnesium, plasma potassium, plasma glucose, and plasma insulin during infusions and for up to one hour following cessation.
What was found
Plasma magnesium levels decreased significantly during both L-adrenaline and salbutamol infusions (with a slower decline observed during salbutamol), with no recovery observed within the 1-hour post-infusion observation window. Plasma potassium levels also fell significantly during both infusions but recovered spontaneously within 30 minutes. Plasma insulin levels showed no significant change compared to placebo for either agent, while plasma glucose increased significantly only during L-adrenaline infusion. The abstract does not provide exact numerical values, effect sizes, or confidence intervals.
Why it matters
These findings suggest that beta-adrenergic stimulation directly drives intracellular shifts in magnesium independently of insulin secretion, providing a physiological explanation for the hypomagnesemia observed in high-stress clinical states like myocardial infarction.
Limits
The study is limited by a very small sample size (n = 8) conducted exclusively in healthy volunteers, limiting generalizability to acutely ill clinical populations. The abstract does not report baseline values, absolute or percentage changes in magnesium, exact statistical test metrics, or long-term clinical endpoints.
Cited by
- supports Whyte et al. demonstrated that adrenaline infusion immediately lowers magnesium levels in humans, and levels remain significantly reduced one hour post-infusion.