Magnesium deficiency produces spasms of coronary arteries: relationship to etiology of sudden death ischemic heart disease.

Isolated coronary arteries from dogs were incubated in Krebs-Ringer bicarbonate isolation and exposed to normal, high, and low concentrations of magnesium in the medium. Sudden withdrawal of magnesium from the medium increased whereas high concentrations of magnesium decreased the basal tension of the arteries. The absence of magnesium in the medium significantly potentiated the contractile responses of both small and large coronary arteries to norepinephrine, acetylcholine, serotonin, angiotensin, and potassium. These data support the hypothesis that magnesium deficiency, associated with sudden death ischemic heart disease, produces coronary arterial spasm.