Sex- and GH-dependent binding of liver nuclear proteins to the CYP2C12 probe. (A) EMSA with the CYP2C12 probe incubated with pooled rat liver nuclear extracts (2 μg of protein per lane) prepared from control (Ctrl) males or females, from hypophysectomized (Hx) females or from Hx females infused with GH for 7 days according to a female-like pattern (Hx + GH). Complexes a, b, c, and d refer to the specific complexes detected in the absence (−), but not in the presence (+), of a 100-fold molar excess of the unlabeled probe. (B) EMSA with the CYP2C12 probe incubated with liver nuclear extracts (2 μg of protein per lane) prepared from five individual males or females. (C) To improve the resolution of the complexes observed in A, the running time of the female samples shown in A was doubled.