Fig. 2. Analysis of growth plates from control and Vhlh null mice with Cre transgenic lines a and b. Hematoxylin and Eosin staining of histological sections of control (A,D,G) and Vhlh null (B,C,E,F,H,I) tibia proximal growth plates at birth. (D-I) Magnification of the resting zone (D-F) and proliferative zone (G-I) of newborn control (D,G) and Vhlh null (E,F,H,I) growth plates. Arrowheads (B,C) indicate areas occupied with atypical enlarged chondrocytes; arrows indicate areas of increased matrix deposition within the Vhlh growth plate.