RESUMEN
<p><b>OBJECTIVE</b>To study the expression and significance of platelet derived growth factor (PDGF) and its receptor (PDGFR) in liver tissues of patients with chronic hepatitis fibrosis and liver cirrhosis.</p><p><b>METHODS</b>The expression, distribution, quantitation, and correlation of PDGF-A, PDGF-B, PDGFR-alpha, PDGFR-beta, and alpha-SMA in the liver tissues were analyzed by immunohistochemical techniques in 21 patients with chronic hepatitis and 42 patients with liver cirrhosis.</p><p><b>RESULTS</b>In the liver tissues of chronic hepatitis and liver cirrhosis, PDGF and its receptor and alpha-SMA mainly distributed in the fibrotic septa and the infiltration area of inflammation, particularly in branch spindle-shaped cells (activated HSC). The expression of PDGF-B and PDGFR-beta was stronger than that of PDGF-A and PDGFR-alpha with a significant difference between them (P<0.05 approximately 0.01). The expression and distribution of alpha-SMA was basically identical with the expression and distribution of PDGF-A, PDGF-B and PDGFR-alpha, PDGFR-beta and quantitative analysis showed a positive correlation (r=0.606, P<0.001).</p><p><b>CONCLUSIONS</b>PDGF and PDGFR play a key role in liver fibrogenesis and development. The biologic effects of PDGF are elicited through activising HSC. Inhibiting PDGF and its receptor is a new approach to the treatment of liver fibrosis.</p>