Into the chemistry of the heart.

In the last few years, advances in nuclear magnetic resonance spectroscopy have allowed medical researchers to gather much information about the molecular chemistry that takes place inside living cells (SN: 10/15/83, p. 250). recently, attention has focused on the isotope phosphorus-31, which occurs naturally in the human body and has a permanent magnetic moment that interacts with an external magnetic field. By detecting the faint signals from these nuclei, researchers can track high-energy phosphate metabolism. These measurements provide valuable diagnostic information about various human muscular and brain disorders without the use of ionizing radiation like X-rays and without cutting open a body or inserting probes. Now, similar measurements have been recorded for a living human heart.

Using a new technique called depth-resolved surface coil spectroscopy, Paul A. Bottomley of the General Electric Research and Development Center in Schenectady, N.Y., obtained phosphorus spectra from the heart of a volunteer. These spectra showed the relative amounts of inorganic phosphorus and the metabolites phosphocreatine and adenosine triphosphate -- normally present in minute quantities and very difficult to detect. Changes in the ratios of these substances, which are involved in the transfer of energy in licing cells, often mirror the effects of heart disease. Bottomley's report appears in the Aug. 23 SCIENCE.