Figure 3.

Photomicrographs showing the effect of paeonol on rat liver tissues stained with H&E in methotrexate (MTX)-induced hepatotoxicity (×100 and ×400). The tissue of the control group (a1) showed typical morphological features of hepatic cells with normal lobular architecture and normal central veins (CV). Similarly, the liver tissues of the paeonol group (b1) showed a normal hepatic structure. The liver tissues of both the control and paeonol groups (a2,b2) showed central veins (CV) which appeared to be lined by flat endothelial cells (double arrows), surrounded by cords of polygonal hepatocytes with granular cytoplasm and central, rounded, vesicular nuclei (blue arrows). Some cells appeared to be binucleated (green arrows). The blood sinusoids (S) are lined by Kupffer cells (yellow arrows). Additionally, the investigated liver tissues of the two groups showed branches of portal veins (PV) and bile ductules (BD) seen at a portal area (squares) (a3,b3). The liver tissues of the MTX-treated rats showed a disturbed lobular architecture with dilated central veins (CV) and blood sinusoids (S), and the cells have darkly stained nuclei with deeply stained cytoplasm (blue arrow) (c1,c2). Moreover, the liver tissues of the MTX-treated rats showed dilated bile ductules (BD) and a dilated portal vein (PV) surrounded by cellular infiltrations (circle) (c3). The microscopic examination of the liver tissues of the paeonol + MTX group showed a normal lobular architecture with apparently normal central veins (CV), except for a focal congested blood sinusoid (S) (d1). In the same group, the hepatocytes appeared to be polygonal with acidophilic cytoplasm and vesicular nuclei (blue arrow) (d2). Furthermore, the liver tissues of the paeonol + MTX group showed some binucleated cells (green arrow) and a few darkly stained nuclei with deeply stained cytoplasm (d2). In the same group, the portal vein (PV) and bile ductules (BD) have a normal appearance (d3).