Vasodilation in JAK2^V617F mice. (Ai) Representative images of the macroscopic aspect of mesenteric vessels from VavCre/JAK2^V617F (KI), EPO-treated, and TPO^high mice. Bars represent 5 mm. (Aii) Diameters of mesenteric VavCre/JAK2^V617F vessels (KI) and matched controls (CTR) (n = 12). ***P < .0001. (B) Representative images showing that the increase in diameter of mesenteric vessel of SCLCreER^t/JAK2^V617F mice appeared 60 days (D60) after treatment by tamoxifen. (C) Representative transverse sections (n = 3) of the aorta from 1 WT and 1 VavCre/JAK2^V617F (hematoxylin and eosin staining). Bars represent 500 µm.