Figure 4.

(a,b) Histopathological examination of the pulmonary artery (same cat as Figure 3). (a) The tunica media (TM) of the right pulmonary artery is dissected by haemorrhage (*). Haematoxylin and eosin stain, × 25 magnification. TA = tunica adventitia. (b) Marked and multifocal fibrosis (*) of the tunica intima with disorganisation/ fragmentation of the elastic fibres and fibrous tissue deposition (arrowhead) in the right pulmonary artery. Picrosirius red stain, × 100 magnification. Images courtesy of Ilaria Biasato and Laura Chiappino