THE EFFECTS OF TUMOR-NECROSIS-FACTOR-ALPHA ON CIRCULATING AMINO-ACIDSIN THE PREGNANT RAT

The administration of an acute dose (6 nmol) of tumour necrosis factor -alpha (TNF-alpha) to 20-day pregnant rats resulted in important chang es in the circulating concentration of maternal blood amino acids. The main changes concern increases in the concentration of neutral (alani ne, glycine, threonine, proline), branched-chain (valine, leucine, iso leucine), basic (lysine, histidine), aromatic (phenylalanine) and acid ic (aspartate and glutamate) amino acids. The cytokine treatment also increased the total concentration of circulating amino acids. In contr ast, the cytokine did not promote any changes in the concentration of amino acids in the fetal circulation. The results suggested support th at TNF-alpha may be responsible for impaired fetal growth as a consequ ence of a decrease in the transplacental passage of amino acids.