The processes that control energy homeostasis are extremely complex and involve /nteractions between peripheral organs, the hypothalamus and the brainstem, as well as inputs from sensory and reward centres of the brain. Researchers have come a long way in recent years in elucidating the networks that control energy balance, but recent transgenic models have shown that over-emphasis may have been put on the arcuate nucleus Research is now shifting to extra-arcuate sites'including the ventromedial nucleus (VMN) which, unlike characterised in terms of its cellular phenotypes.