NPY and Insulin resistance: 1983) have shown that adrenergic receptors antagonism does not modify the decrease in hepatic glucose following administration of insulin in the VMH. Nevertheless, we cannot neglect the involvement of sympathetic output in controlling of the HVGC via the central action of insulin, and in fact it has been showing elsewhere that ICV injection of neuropeptide Y-induced insulin resistance and changes in endogenous glucose production via activation of sympathetic output to the liver (Van den Hoek et al. 2008).