IRS1/2 mediate the effects of IGF1 on the differentiation of antler chondrocytes. (A) Effects of IRS1 siRNA on the expression of IRS1, IHH and IGF1. (B) Effects of IRS2 siRNA on the expression of IRS2, IHH and IGF1. (C) IRS1 expression in antler chondrocytes treated with rIGF1 for 1, 3, 6, 12 and 24 h. (D) IRS2 expression in antler chondrocytes treated with rIGF1 for 1, 3, 6, 12 and 24 h. (E) Expression of IRS1 and IRS2 after antler chondrocytes were treated with rIGF1, or rIGF1 and PQ401. (F) Effects of IGF1 overexpression on the expression of IRS1 and IRS2. (G) Effects of IGF1 siRNA on the expression of IRS1 and IRS2. (H) IRS1 mediated the effects of IGF1 on the expression of IHH. After transfection with IRS1 siRNA and addition of rIGF1, the expression of IHH was determined by real-time PCR. (I) IRS2 mediated the effects of IGF1 on the expression of IHH. siIRS1, IRS1 siRNA; siIRS2, IRS2 siRNA.