Ad lib fed 300-350 g Wistar rats were implanted with cannulae in the external carotid artery, the pancreato-duodenal and hepatic vein 5-7 days prior to oral administration of ethanol sufficient to elevate blood ethanol to 30-40 mM. We then determined the concentration of liver 3H20, 14C-insulin and 51Cr-red space, the concentration of 1-Alanine and 1- Glutamate -, NH4+ and inorganic electrolytes within the three vessels and within freeze-clamped liver as well as the potential (EN) between extra- and intracellular phases of liver. The calculated deltaG[Na=} between hepatic vein/liver increased from +11.2 to +14.5 kJ/mol. The deltaG[1- Glutamate-] gradient between hepatic vein/liver was about -13kJ/mol with or without ethanol suggesting that the reaction was close to near- equilibrium with the energy of sodium. The deltaG[1-Alanine] between hepatic vein/liver differed both in magnitude and direction of change after ethanol treatment from ~G[Na+] hepatic vein/liver; it was -4.23 kJ/mol in control animals and decreased to-2.6 kJ/mol after ethanol treatment. The result is compatible with a net 1-Alanine/NH4+ exchange rather than Na+ linked 1-Alanine co-transport. The sum of ~G[1-Glutamine] hepatic vein/liver + ~[NH4+] hepatic vein/liver was found to equal deltaG[Na+] hepatic vein/liver. Oral administration of ethanol inhibited uptake of arterial 1-Glutamine by intestine, decreased the hepatic ~G 1- Alanine portal vein/liver to 0, increased the deltaG1-Glutamine portal vein/liver and its co-transport partner deltaG[Na+] hepatic vein/liver with which it appeared to be in near-equilibrium according to the intrahepatic glutamine synthase (EC 6.3.1.2) reaction from 5.56x10-9 M, a value close to 1.20x10-9 M expected at near-equilibrium to a value of about 1x10-8 M.
