Examining a potential functional role for growth hormone secretagogue receptors in the hippocampus, Diano and colleagues (Diano et al., 2006), demonstrate novel actions of the orexigenic peptide ghrelin in hippocampal synaptic architecture, LTP, and learning and memory. These data suggest functional links between metabolic signaling and higher neural function.

Of several circulating hormones that act on hypothalamus to affect body energy balance, only ghrelin is also expressed in hypothalamic neurons. From the studies of Horvath and colleagues appearing in this issue of Neuron, it appears that neuronal ghrelin acts presynaptically to stimulate release of the orexigenic peptide, neuropeptide Y, and other neurotransmitters, thus defining a new and subt...

BACKGROUND Psychiatric patients often require chronic treatment with antipsychotic drugs, and while rats are frequently used to study antipsychotic-induced metabolic adverse effects, long-term exposure has only partially mimicked the appetite-stimulating and weight-inducing effects found in the clinical setting. Antipsychotic-induced effects on serum lipids are also inconsistent in rats, but in...

Estradiol participates in the control of energy homeostasis, as demonstrated by an increase in food intake and in body weight gain after ovariectomy in rats. In the present study, female Wistar rats (200-230 g, N = 5-15 per group), with free access to chow, were individually housed in metabolic cages. We investigated food intake, body weight, plasma leptin levels, measured by specific radioimmu...

23 24 Goebel-Stengel M, Stengel A, Wang L, Taché Y. Orexigenic response to tail pinch: role of 25 brain NPY1 and corticotropin releasing factor receptors. Am J Physiol Regul Integr Comp Physiol 26 Tail pinch stimulates food intake in rats. We investigated brain mechanisms of this response and 27 the influence of repeated exposure. Sprague-Dawley rats received acute (5 min) or repeated (5 28 min...

OBJECTIVE The role of the central nervous system in mediating metabolic effects of Roux-en-Y gastric bypass (RYGB) surgery is poorly understood. Using a rat model of RYGB, we aimed to identify changes in gene expression of key hypothalamic neuropeptides known to be involved in the regulation of energy balance. METHODS Lean male Sprague-Dawley rats underwent either RYGB or sham surgery. Body w...

Neurons that synthesize melanin-concentrating hormone (MCH) may modulate arousal and energy homeostasis. The scattered MCH neurons have been difficult to study, as they have no defining morphological characteristics. We have developed a viral approach with AAV for selective long-term reporter gene (GFP) expression in MCH neurons, allowing the study of their cellular physiology in hypothalamic s...