Figure 5

MCT-induced increases in both medial wall thickness and muscularization of pulmonary arteries were attenuated through the HMGB1 inhibition by GLY treatment. (A, B) Elastica-eosin staining showing that the medial area between the lamina elastica interna and externa (deep violet) increased in the MCT group when compared with the normal control group (*p <0.001). Treatment with GLY attenuated the medial change induced by MCT injection (†p <0.001). GLY treated alone without MCT yielded no significant difference in medial wall thickness when compared with that of control rats (p = 0.501). (C, D) The degree of muscularization of pulmonary arteries was observed via immunostaining of α-SMA (brown) and vWF (purple). In the MCT group, the proportion of muscularized pulmonary arteries increased when compared with the control group (■p <0.001). GLY treatment attenuated this MCT-induced muscularization of pulmonary arteries (♦p <0.001). GLY treated alone without MCT yielded no significant difference in pulmonary artery muscularization when compared with that of control rats (p = 0.262). Data are presented as means ± SEM.