The hypothalamic paraventricular nucleus (PVN) is the major brain site that synthesizes hypophysiotropic corticotropin-releasing hormone (CRH) and arginine vasopressin (AVP) to initiate the neuroendocrine stress response to various external or internal challenges. Additional cell clusters in the PVN give rise to long descending projections to the brain stem and spinal cord. These neurons are in the position to govern stress-related autonomic responses. Retrograde tracing studies using neurotropic viruses identified these neurons as elements of neurocircuits regulating sympathetic outflow to various organs affected by stress. Activation marker c-fos revealed challenge-specific activation of neurosecretory and autonomic-related neurons in the PVH. Much is known about the location, chemical signatures and secretory capabilities of hypothalamic effector neurons that govern the neuroendocrine stress response; however, how these come to be situationally linked to autonomic command neurons to form operational circuits during challenge, is poorly understood. There is a bidirectional communication between neurocircuits regulating feeding and stress. On one hand, stress has a significant impact on food intake and metabolism, while energy status and availability of fuels affect the sensitivity to stressors, expression of hypothalamic stress-related neuropeptides as well as determining coping strategies. As a recent example from our laboratory, chronic exposures to sucrose of adrenalectomized (ADX) or control rats resulted in activation of AVP gene expression in the autonomic-related projection neurons of the PVH. However, this challenge did not affect CRH and AVP transcription induced by the withdrawal of the steroid negative feedback signal in the neurosecretory neurons of the medial dorsal parvocellular subdivision. AVP hnRNA induction during chronic sucrose loading was confined to the ventral medial parvocellular subdivision; however, cells in the dorsal parvocellular part of the PVN that project to the spinal cord were not responsive to metabolic challenge. Autonomic-related neurons in the PVN are involved in the regulation of different fat depots. White (WAT) and brown (BAT) adipose tissue represent functionally distinct compartments of lipid storage and fuel consumption, respectively. We have applied dual viral transneuronal tracing strategy using isogenic recombinant strains of the pseudorabies virus to identify neurons in the rat hypothalamus that innervate WAT and/or BAT. In addition to various brain stem neurons, a high number of double-labelled neurons were identified in the autonomic-related subdivisions of the PVN, suggesting coordinated control of fat depots by autonomic command neurons during challenge.