Albumin synthesis and effect of betamethasone on albumin synthesis in perfused liver of normal and ccl4-intoxicated rats

Abstract

Synthesis of plasma albumin was studied in perfused liver of normal and CCl₄-intoxicated rats, using¹⁴C-bicarbonate method. 1. In normal liver, albumin synthesis averaged 5.6 mg/hr/100 g body weight. 2. In CCl₄-intoxicated liver, albumin synthesis decreased to 4.6 mg at acute stage, but restored to 5.1 mg at non-septal fibrotic stage. At septal fibrotic, cirrhotic and cirrhotic stage with ascites, the synthesis rate averaged 4.5 mg, 4.1 mg and 3.2 mg, respectively. From these results, it is inferred that albumin synthesis rate decreases in accordance with the progress of the liver injury. 3. Effect of betamethasone on plasma albumin synthesis in perfused rat liver was investigated. Albumin synthesis rate in normal liver averaged 5.4 mg, and after addition of betamethasone, the rate increased to 8.7 mg. In CCl₄-intoxicated liver, the synthesis rate at acute, chronic and cirrhotic stage averaged 4.3 mg, 3.3 mg and 2.8 mg, respectively. The rate after addition of betamethasone increased to 7.3 mg, 5.5 mg and 4.5 mg, respectively. From these results obtained, it is inferred that betamethasone increases plasma albumin synthesis in both normal and CCl₄-intoxicated liver. 4. In normal liver, actinomycin-D did not inhibit basal albumin synthesis, but inhibited the increase of albumin synthesis by betamethasone, when actinomycin-D was added together with betamethasone. From these facts, it is concluded that betamethasone is able to induce albumin synthesis.