Figure 5.
Effect of somatostatin (10−6–10−9 mol l−1) on de novo synthesis of collagen types I (a) and III (b), and of smooth muscleα-actin (c) by activated stellate cells. Connective tissue proteins from medium and cell layer were labelled with Trans-35S-label and analysed by immunoprecipitation and SDS–PAGE (left panels). Radioactivity was quantified by Phosphor Imaging (right panels). Medium is presented in grey bars, cell lysate in black bars. Since smooth muscle α-actin is not secreted in the medium, smooth muscle α-actin was only studied in the cell layer. Control values within each experiment were normalized at 100%. Results are expressed as means±standard deviation (n=3). Only treatment with somatostatin 10−9 mol l−1 resulted in a statistically significant difference as compared to control (*).