In mammals, the major pacemaker controlling circadian rhythmicity is located in the hypothalamic suprachiasmatic nuclei. Although there is evidence for the presence of a hypothalamic circadian oscillator in birds from lesioning studies, neuroanatomical, neurochemical and functional investigations have failed to identify its exact location. Two cell groups in the avian hypothalamus have been sho...

The hypothalamus is a forebrain structure critically involved in the organization of defensive responses to aversive stimuli. Gamma-aminobutyric acid (GABA)ergic dysfunction in dorsomedial and posterior hypothalamic nuclei is implicated in the origin of panic-like defensive behavior, as well as in pain modulation. The present study was conducted to test the difference between these two hypothal...

Recent studies have revealed that insulin signaling in pancreatic β-cells and the hypothalamus is critical for maintaining nutrient and energy homeostasis, the failure of which are hallmarks of metabolic syndrome. We previously reported that forkhead transcription factor forkhead box-containing protein of the O subfamily (FoxO)1, a downstream effector of insulin signaling, plays important roles...

Carnitine palmitoyl-CoA transferase-1B is a mitochondrial enzyme in the fatty acid oxidation pathway. In a previous study, CPT1B was identified as differentially expressed in the hypothalamus of two lines of chickens established by long-term selection for high (HWS) or low (LWS) body weight. Mammals have three paralogs (CPT1a, b and c) while nonmammalian vertebrates only have two (CPT1A, B). CP...

Hypothalamus-pituitary-adrenal (HPA) hyperactivity is observed in many patients suffering from depression and the mechanism underling the dysfunction of HPA axis is not well understood. Chronic stress has a causal relationship with the hyperactivity of HPA axis. Stress induces the over-synthesis of glucocorticoids, which will arrive at all the body containing the brain. It is still complicated ...

Increased sympathetic outflow from the central nervous system to the periphery may contribute to the initiation of hypertension in spontaneously hypertensive rats (SHR). As this alteration in sympathetic activity may be mediated in part by a-adrenergic receptors in the central nervous system, the current study examined aradrenergic receptors in various brain areas of SHR and normotensive Wistar...

Bacterial endotoxin induces fever by causing the release of interleukin (IL)-1β into the circulation or the brain. IL-1β is believed to mediate fever via triggering the production and/or release of IL-6 in the hypothalamus. The present study examined whether IL-1β and IL-6 in the hypothalamus of the rat are also involved in fever during bacterial sepsis caused by cecal ligation and puncture (CL...

Neuropeptide Y (Npy) is an intricate neuropeptide regulating numerous physiological processes. It a highly conserved peptide known to improve feed intake in many vertebrates, including fishes. To enlighten the mechanism of Npy spotted scat control, we cloned and identified cDNA sequence. We further examined its expression some tissues explored effects at different time frames (hours days). Here...

Introduction: Arginine-phenylalanine-amide-related peptide-3 (RFRP-3) and kisspeptin are believed to be inhibitor and stimulator of gonadotropin releasing hormone (GnRH) secretion, respectively. The aim of the present study was to compare the effect of lactation on the expression of RFRP-3 mRNA in dorsomedial hypothalamic nucleus (DMH) and KiSS-1 mRNA in arcuate nucleus (ARC) of hypothalamus...

It has long been suggested that the secretion of the anterior pituitary hormones is under the control of the hypothalamus (Green and Harris, 1947; Harris, 1955). Early studies of the vasculature of the hypothalamic-hypophyseal system in birds and mammals described a portal system of capillaries in close contact with neurosecretory cells of the median eminence of the hypothalamus and draining to...