We describe a hypothalamus-specific mRNA that encodes preprohypocretin, the putative precursor of pair peptides share substantial amino acid identities with gut hormone secretin. The hypocretin (Hcrt) protein products are restricted to neuronal cell bodies dorsal and lateral hypothalamic areas. fibers these neurons widespread throughout posterior hypothalamus project multiple targets in other areas, including brainstem thalamus. Hcrt immunoreactivity is associated large granular vesicles at...

The novel neuropeptides called hypocretins (orexins) have recently been identified as being localized exclusively in cell bodies a subregion of the tuberal part hypothalamus. structure hypocretins, their accumulation vesicles axon terminals, and excitatory effect on cultured hypothalamic neurons suggest that function intercellular communication. To characterize these peptides further to help understand what physiological functions they may serve, we undertook an immunohistochemical study...

Abstract The receptor mGluR5 is a metabotropic glutamate with messenger RNA abundantly present throughout cortex, hippocampus, and caudate/putamen that also coupled to phosphatidyl inositide hydrolysis calcium mobilization. In this study, the distribution of was examined in rat brain by immunocytochemistry. antibody utilized highly specific does not cross react most closely related other receptor, as determined Western blot analysis nonneuronal cells transfected coding sequences. widely...

Hypocretin has been identified as a regulator of metabolic and endocrine systems. Several brain regions involved in the central regulation autonomic processes or attention are targets extensive hypocretin projections. The most dense arborization axons brainstem was detected locus coeruleus (LC). Multiple labeling immunocytochemistry revealed massive synaptic innervation catecholaminergic LC cells by axon terminals rats monkeys. In both species, all tyrosine hydroxylase-immunopositive...

Abstract To study the organization and distribution of inhibitory amino acid neurotransmitter GABA in medial hypothalamus, we used a postembedding immunocytochemical approach with colloidal gold. Quantitative analysis showed that half (49%) all synapsing boutons studied were immunoreactive for GABA, based on immunogold staining suprachiasmatic, arcuate, supraoptic, paraventricular nuclei. This was corroborated pre‐embedding peroxidase immunostaining antisera against glutamate decarboxylase,...

A new orexigenic peptide called hypocretin (orexin) has recently been described in neurons of the lateral hypothalamus and perifornical area. The medial have loosely satiety feeding centers brain, respectively. Approximately one-third all hypothalamic tested, but not hippocampal neurons, show a striking nanomolar sensitivity to hypocretin. As studied with calcium digital imaging fura-2, raises cytoplasmic via mechanism based on G-protein enhancement influx through plasma membrane channels....

Glutamate has been found to play an unexpectedly important role in neuroendocrine regulation the hypothalamus, as revealed converging experiments with ultrastructural immunocytochemistry, optical physiology a calcium-sensitive dye, and intracellular electrical recording. There were large amounts of glutamate boutons making synaptic contact neurons arcuate, paraventricular, supraoptic nuclei. Almost all medial hypothalamic responded agonists quisqualate kainate consistent increase calcium. In...

Hypocretin (orexin) is synthesized by neurons in the lateral hypothalamus and has been reported to increase food intake regulate neuroendocrine system. In present paper, long descending axonal projections that contain hypocretin were found innervate all levels of spinal cord from cervical sacral segments, as studied mouse, rat, human not previously described. High densities innervation are regions related modulation sensation pain, notably marginal zone (lamina 1). Innervation...

Hypocretin (orexin) has recently been shown to increase feeding when injected into the brain. Using both rat and primate brains, we tested hypothesis that a mechanism of hypocretin action might be related synaptic regulation neuropeptide Y (NPY) system. Hypocretin-immunoreactive terminals originating from lateral hypothalamus make direct contact with neurons arcuate nucleus not only express NPY but also contain leptin receptors. In addition, hypocretin-containing receptor immunoreactivity....

Abstract The internal structure of the suprachiasmatic nucleus (SCN) was studied qualitatively and quantitatively in several hundred rat brains with a variety methods including types Golgi impregnations, Nissl stains, horseradish peroxidase application, electron microscopy. One has volume about 0.068 mm 3 contains close to 8,000 neurons. Dorsomedially, cells tend be smaller more tightly packed than ventrolaterally; significantly somatic appositions occur dorsomedial SCN other parts nucleus....

The hypocretins (hcrt1 and hcrt2) are expressed by a discrete population of hypothalamic neurons projecting to many regions the CNS, including dorsal raphe nucleus (DRN), where serotonin (5-HT) concentrated. In this study, we investigated responses hcrts in 216 physiologically identified 5-HT non-5-HT DRN using intracellular whole-cell recording rat brain slices. Hcrt1 hcrt2 induced similar amplitude dose-dependent inward currents most tested (EC50, approximately 250 nm). This current was...

Melanin concentrating hormone (MCH) is a cyclic neuropeptide present in the hypothalamus of all vertebrates. MCH implicated number behaviors but direct evidence lacking. To selectively stimulate neurons gene for light-sensitive cation channel, channelrhodopsin-2, was inserted into wild-type mice. Three weeks later were stimulated 1 min every 5 24 h. A 10 Hz stimulation at start night hastened sleep onset, reduced length wake bouts by 50%, increased total time non-REM and REM night, intensity...

The neuronal substrate for binge eating, which can at times lead to obesity, is not clear. We find that optogenetic stimulation of mouse zona incerta (ZI) γ-aminobutyric acid (GABA) neurons or their axonal projections paraventricular thalamus (PVT) excitatory immediately (in 2 3 seconds) evoked binge-like eating. Minimal intermittent led body weight gain; ZI GABA neuron ablation reduced weight. generated 35% normal 24-hour food intake in just 10 minutes. cells were excited by deprivation and...

Zika virus (ZIKV), a positive-sense RNA flavivirus, has attracted considerable attention recently for its potential to cause serious neurological problems, including microcephaly, cortical thinning, and blindness during early development. Recent findings suggest that ZIKV infection of the brain can occur not only very stages development, but also in later fetal/early neonatal maturation. Surprisingly, after peripheral inoculation immunocompetent mice on day birth, first cells targeted...

1. Gramicidin-perforated patch clamp recording was employed to study GABA-mediated responses in rat hypothalamic neurones (n = 102) with an intracellular Cl- concentration unaltered by the pipette solution. 2. In young cultures after 1-7 days vitro (DIV), GABA induced depolarizing membrane potentials (+16.5 +/- 1.3 mV) that often surpassed threshold for firing of action (-42 1 and resulted increase neuronal activity. The were dose dependent. necessary evoke half-maximal depolarization (EC50)...

GABA is the dominant inhibitory neurotransmitter in CNS. By opening Cl − channels, generally hyperpolarizes membrane potential, decreases neuronal activity, and reduces intracellular Ca 2+ of mature neurons. In present experiment, we show that after trauma, GABA, both synaptically released exogenously applied, exerted a novel opposite effect, depolarizing neurons increasing . Different types trauma were effective included neurite transection, replating, osmotic imbalance, excess heat. The...

The neuropeptide kisspeptin is necessary for reproduction, fertility, and puberty. Here, we show strong innervation of hypothalamic anorexigenic proopiomelanocortin (POMC) cells, coupled with a robust direct excitatory response by POMC neurons ( n > 200) to kisspeptin, mediated mechanisms based on activation sodium/calcium exchanger possibly opening nonselective cation channels. actions cells were corroborated quantitative PCR data showing receptor GPR54 expression in the arcuate nucleus,...

Abstract The magnocellular and parvocellular regions of the rat hypothalamic paraventricular nucleus (PVN) were examined in several hundred brains. Converging qualitative quantitative anatomical methods, including Golgi impregnations, Nissl stains, silver immunocytochemistry used to study intrinsic organization PVN with light, scanning, transmission electron microscopy. A computer‐assisted analysis dendritic branching patterns was examine total length, center mass, orientation tree, other...