Effects of various catecholamines on high-energy phosphates of rat liver and brain during hemorrhagic shock measured by31p-NMR spectroscopy

Abstract

The effects of dopamine, epinephrine and norepinephrine on energy metabolism as well as intracellular pH in rat liver and brain during hemorrhagic shock were examined by in vivo 31P-NMR spectroscopy. The hemorrhagic shock was induced by arterial bleeding to a mean arterial pressure (MAP) of 30-40 mmHg. Upon the induction of hemorrhagic shock, there was a dramatic fall in adenosine triphosphate (ATP) and a rise in inorganic phosphate (Pi) in the liver. The intracellular pH indicated severe acidosis. However, no change in these parameters was observed in the brain during hemorrhagic shock. After infusion of the above catechollamines following 10 min of hemorrhagic shock, MAP increased to 90-100% of its control value. Only dopamine improved hepatic energy metabolism, whereas brain energy metabolism was not affected by any of them. This suggests that dopamine protects liver function during hemorrhagic shock without affecting brain energy metabolism.

Hemorrhagic shock-induced cerebral bioenergetic imbalance is corrected by pharmacologic treatment with EF24 in a rat model

“…Our observations of the effect of shock on energy metabolites are different from those made by Okuda et al and Mongan et al (Okuda et al 1989, Mongan et al 2001). Both these studies reported ATP remaining unchanged, but the measurements were limited to the acute phase (< 2 h) of shock.…”