GH protein in the arcuate nucleus of the hypothalamus. (A) A representative blot is shown. (B) Densitometry data from the blots is presented. Adult mice from the four core genotypes—XY males (black bars), XX males (horizontal striped bars), XX females (white bars), and XY females (diagonal striped bars)—were gonadectomized and treated with estradiol (E). N = 6 in each group. The single asterisk signifies significant effect of sex chromosome complement (P < 0.05).