The aim of the study was to compare amino acid concentrations in liver and muscle interstitium in the early postoperative phase after partial hepatectomy (PH) and laparotomy (LAP). After institutional approval 12 adult male Wistar rats were divided into 2 groups. Group I: LAP was performed under ether anaesthesia and then two microdialysis probes CMA 20 (CMA Microdialysis, Sweden, cut off 20 kDa) were inserted into the liver lobe and into paravertebral skeletal muscle. Group II: PH was performed and then 2 microdialysis probes were inserted into the same sites. The microdialysis probes in freely moving animals were perfused at a rate of 0.6 ml/min with sterile saline solution by means of an infusion pump LD 20. Microdialysis samples were collected during 18 hours. Amino acid concentrations (nmol/l) were estimated in microdialysates using the HPLC system (Hewlett Packard) with fluorimetric detection. The concentrations of amino acids were lower in liver interstitium in comparison with muscle interstitium with the exception of branched chain amino acids leucine and isoleucine. The concentrations of leucine and isoleucine were higher in liver interstitium 2 and 6 hours after PH and 6 hours after LAP.

        Key words: partial hepatectomy, microdialysis, amino acids, rat.