Growth hormone (GH), which suppresses obesity, is also linked to hypothalamic ER-α through control of GH neurons in the arcuate nucleus [70]. GH suppresses PPARα activation [71] and targets many liver genes affected by Cyp1b1 deletion. Male-selective expression derives from regulated, intermittent GH pulses, which contrast a continual, moderate secretion in female mice [72]. The minimal effect of Cyp1b1 deletion on the major functional target of GH in the liver, IGF-1 [73], suggests that Cyp1b1 is not simply elevating GH levels.
