Search

Phosphorus-31 surface coil spectroscopy has been used to study the effects of L-ethionine administration on the hepatic metabolism of the anesthetized Sprague-Dawley rat. ATP levels were found to decrease by approximately 30% 3 to 4 hr after administration of 1 mg/g body wt of L-ethionine to the anesthetized rat by gastric gavage. ATP levels returned to control values approximately 8 hr postadministration. The relatively small decrease in ATP level was confirmed by extraction and conventional enzyme assay and is a consequence of the mode of administration of the ethionine. Hepatic inorganic phosphate levels rose concomitantly with the ATP fall. There were no significant changes in either cellular pH or Mg2+ levels as monitored by the 31P shifts of sensitive metabolites. In vivo 31P NMR spectroscopy provides a promising approach to study the effects of hepatotoxicants on cellular ATP, pH, and Mg levels.

The avian egg is an isolated system where embryonic development can easily be studied. Furthermore, the system can be subjected to various environmental constraints. Its size is such that it can easily be accommodated in most NMR instruments. This is demonstrated by a recent 31P-NMR surface coil experiment where the increase of embryo size and development could be judged by the levels of ATP and phosphocreatine (Belton, P.S., Gordon, R.E., Jones, J.M. and Shaw, D. (1983) Br. Poult. Sci. 24, 429–433).