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[english] Interruption of oxygen availability and re-oxygenation at birth implies a severe metabolic insult, affecting the development of the central nervous system (CNS), increasing its vulnerability to challenges occurring at adult stages. It has been reported that perinatal asphyxia produces regionally specific neuronal decrease and neurite atrophy in basal ganglia, and hippocampus. In hippocampus, a concomitant increase of neurogenesis and neurite hypertrophy has also been observed. The potential neuroprotection of nicotinamide, a non-selective inhibitor of poly (ADP-ribose) polymerase (PARP-1), has been investigated, finding functional and morphological improvements when administered 24h after the insult (0.8 mmol/kg, i.p., 24, 48 and 72 h after birth.). The main effect of nicotinamide has been seen in neostriatum, preventing an asphyxia-induced decrease of the number of nNOS cells, and nNOS- and dopamine-like neurite atrophy. The present results support the idea that nicotinamide can prevent the effects elicited by a sustained energy-failure condition, as occurring during perinatal asphyxia, enlightening the enzyme PARP-1 as a novel target for neuronal protection. The support by FONDECYT, ICBM-Enlace, DAAD-CONICYT Programme-2007 grants is acknowledged.

Introduction Acute pain (nociception) is a physiologically relevant sensation aimed at alerting an individual to, and thus limiting, tissue damage upon contact with harmful stimuli. In turn, chronic pain is [...], Pain signals are transmitted by multisynaptic glutamatergic pathways. Their first synapse between primary nociceptors and excitatory spinal interneurons gates the sensory load. In this pathway, glutamate release is orchestrated by [Ca.sup.2+]-sensor proteins, with N-terminal EF-hand [Ca.sup.2+]-binding protein 2 (NECAB2) being particular abundant. However, neither the importance of [NECAB2.sup.+] neuronal contingents in dorsal root ganglia (DRGs) and spinal cord nor the function determination by NECAB2 has been defined. A combination of histochemical analyses and single- cell RNA-sequencing showed NECAB2 in small- and medium-sized C- and A[delta] D-hair low-threshold mechanoreceptors in DRGs, as well as in protein kinase C [gamma] excitatory spinal interneurons. NECAB2 was downregulated by peripheral nerve injury, leading to the hypothesis that NECAB2 loss of function could limit pain sensation. Indeed, [Necab2.sup.-/-] mice reached a pain-free state significantly faster after peripheral inflammation than did WT littermates. Genetic access to transiently activated neurons revealed that a mediodorsal cohort of [NECAB2.sup.+] neurons mediates inflammatory pain in the mouse spinal dorsal horn. Here, besides dampening excitatory transmission in spinal interneurons, NECAB2 limited pronociceptive brain-derived neurotrophic factor (BDNF) release from sensory afferents. Hoxb8-dependent reinstatement of NECAB2 expression in [Necab2.sup.-/-] mice then demonstrated that spinal and DRG NECAB2 alone could control inflammation-induced sensory hypersensitivity. Overall, we identify NECAB2 as a critical component of pronociceptive pain signaling, whose inactivation offers substantial pain relief.

Morphine-induced analgesia and antinociceptive tolerance are known to be modulated by interaction between [delta]-opioid receptors (DORs) and [mu]-opioid receptors (MORs) in the pain pathway. However, evidence for expression of DORs in nociceptive small-diameter neurons in dorsal root ganglia (DRG) and for coexistence of DORs with MORs and neuropeptides has recently been challenged. We now report, using in situ hybridization, single-cell PCR, and immunostaining, that DORs are widely expressed not only in large DRG neurons but in small ones and coexist with MORs in peptidergic small DRG neurons, with protachykinin-dependent localization in large dense-core vesicles. Importantly, both DOR and MOR agonists reduce depolarization-induced [Ca.sup.2+] currents in single small DRG neurons and inhibit afferent C-fiber synaptic transmission in the dorsal spinal cord. Thus, coexistence of DORs and MORs in small DRG neurons is a basis for direct interaction of opioid receptors in modulation of nociceptive afferent transmission and opioid analgesia. dorsal root ganglion | spinal cord | peptides | pain | tolerance doi/ 10.1073/pnas.1008382107

The [Ca.sup.2+]-binding proteins (CBPs) parvalbumin, calbindin, and calretinin are phenotypic markers of terminally differentiated neurons in the adult brain. Although subtle phylogenetic variations in the neuronal distribution of these CBPs may occur, morphologically and functionally diverse subclasses of interneurons harbor these proteins in olfactory and corticolimbic areas. Secretagogin (scgn) is a recently cloned CBP from pancreatic [beta] and neuroendocrine cells. We hypothesized that scgn is expressed in the mammalian brain. We find that scgn is a marker of neuroblasts commuting in the rostral migratory stream. Terminally differentiated neurons in the olfactory bulb retain scgn expression, with scgn being present in periglomerular cells and granular layer interneurons. In the corticolimbic system, scgn identifies granule cells distributed along the dentate gyrus, indusium griseum, and anterior hippocampal continuation emphasizing the shared developmental origins, and cytoarchitectural and functional similarities of these neurons. We also uncover unexpected phylogenetic differences in scgn expression, since this CBP is restricted to primate cholinergic basal forebrain neurons. Overall, we characterize scgn as a neuronspecific CBP whose distribution identifies neuronal subtypes and hierarchical organizing principles in the mammalian brain. cortex | development | interneuron | neurogenesis | stem cell doi/10.1073/pnas.0912484106

Increasing efferent renal sympathetic nerve activity (ERSNA) increases afferent renal nerve activity (ARNA), which in turn decreases ERSNA via activation of the renorenal reflexes in the overall goal of maintaining low ERSNA. We now examined whether the ERSNA-induced increases in ARNA are modulated by dietary sodium and the role of endothelin (ET). The ARNA response to reflex increases in ERSNA was enhanced in high (HNa)- vs. low-sodium (LNa) diet rats, 7,560 [+ or -] 1,470 vs. 900 [+ or -] 390% * s. The norepinephrine (NE) concentration required to increase [PGE.sub.2] and substance P release from isolated renal pelvises was 10 pM in HNa and 6,250 pM in LNa diet rats. In HNa diet pelvises 10 pM NE increased [PGE.sub.2] release from 67 [+ or -] 6 to 150 [+ or -] 13 pg/min and substance P release from 6.7 [+ or -] 0.8 to 12.3 [+ or -] 1.8 pg/min. In LNa diet pelvises 6,250 pM NE increased [PGE.sub.2] release from 64 [+ or -] 5 to 129 [+ or -] 22 pg/min and substance P release from 4.5 [+ or -] 0.4 to 6.6 [+ or -] 0.7 pg/min. In the renal pelvic wall, ETB-R are present on unmyelinated Schwann cells close to the afferent nerves and ETA-R on smooth muscle cells. ETA-receptor (R) protein expression in the renal pelvic wall is increased in LNa diet. In HNa diet, renal pelvic administration of the ETB-R antagonist BQ788 reduced ERSNA-induced increases in ARNA and NE-induced release of [PGE.sub.2] and substance P. In LNa diet, the ETA-R antagonist BQ123 enhanced ERSNA-induced increases in ARNA and NE-induced release of substance P without altering [PGE.sub.2] release. In conclusion, activation of ETB-R and ETA-R contributes to the enhanced and suppressed interaction between ERSNA and ARNA in conditions of HNa and LNa diet, respectively, suggesting a role for ET in the renal control of ERSNA that is dependent on dietary sodium. sensory nerves; substance P; [PGE.sub.2]; endothelin A receptors; endothefin B receptors; renal pelvis; norepinephrine

Treatment of neuropathic pain is a major clinical problem. This study shows expression of phospholipase [beta]3 (PLC[beta]3) in mouse and human DRG neurons, mainly in small ones and mostly with a nonpeptidergic phenotype. After spared nerve injury, the pain threshold was strongly reduced, and systemic treatment of such animals with the unselective PLC inhibitor U73122 caused a rapid and long-lasting (48-h) increase in pain threshold. Thus, inhibition of PLC may provide a way to treat neuropathic pain. galanin receptor 2 | nerve injury | neuropeptide | pain treatment | sensory neuron

The neuropeptide galanin R1 receptor (GalR1) was tagged at its C terminus with EGFP (GalR1-EGFP) to study receptor localization and trafficking. In PC12 and HEK293 cells, functional GaIR1-EGFP was expressed on the plasma membrane and internalized into cytoplasmic vesicles after galanin stimulation. The internalization was blocked by 0.4 M sucrose and by silencing of dathrin with siRNA methodology. Internalized GalR1-EGFP and LysoTracker, a lysosomal marker, overlapped in intracellular vesicles after prolonged galanin stimulation. This colocalization was strongly reduced after site-directed mutagenesis of the motif YXXO on the C terminus of GalR1 (where O is a bulky hydrophobic residue and X any amino acid). Taken together, these data suggest that GalR1 is internalized via the clathrin-dependent, endocytic pathway and then, to a large extent, delivered to lysosomes for degradation through the lysosome-targeting signal YXXO. degradation | endocytosis | G protein-coupled receptor | green fluorescent protein | internalization

Neural progenitor proliferation, differentiation, and migration are continually ongoing processes in the subventricular zone (SVZ) and rostral migratory stream (RMS) of the adult brain. There is evidence that peptidergic systems may be involved in the molecular cascades regulating these neurogenic processes, and we examined a possible influence of neuropeptide Y (NPY) and cholecystokinin (CCK) systems in cell proliferation and neuroblast formation in the SVZ and RMS and generation of interneurons in the olfactory bulb (OB). We show that NPY and the Y1 and Y2 receptor (R) proteins are expressed in and surrounding the SVZ and RMS and that Y1R is located on neuroblasts in the anterior RMS. Mice deficient in Y1Rs or Y2Rs have fewer Ki-67-immunoreactive (ir) proliferating precursor cells and doublecortin-ir neuroblasts in the SVZ and RMS than WT mice, and less calbindin-, calretinin-, and tyrosine hydroxylase-ir interneurons in the OB. Mice lacking CCKIRs have fewer proliferating cells and neuroblasts than normal and a shortage of interneurons in the OB. These findings suggest that both NPY and CCK through their receptors help to regulate the proliferation of precursor cells, the amount of neuroblast cells in the SVZ and RMS, and influence the differentiation of OB interneurons. adultneurogenesis | CCKreceptors | neuropeptides | NPY receptors | rostral migratory stream

Increasing efferent renal sympathetic nerve activity (ERSNA) increases afferent renal nerve activity (ARNA). To test whether the ERSNA-induced increases in ARNA involved norepinephrine activating [alpha]-adrenoceptors on the renal sensory nerves, we examined the effects of renal pelvic administration of the [[alpha].sub.1]- and [[alpha].sub.2]-adrenoceptor antagonists prazosin and rauwolscine on the ARNA responses to reflex increases in ERSNA (placing the rat's tail in 49[degrees]C water) and renal pelvic perfusion with norepinephrine in anesthetized rats. Hot tail increased ERSNA and ARNA, 6,930 [+ or -] 900 and 4,870 [+ or -] 670%'s (area under the curve ARNA vs. time). Renal pelvic perfusion with norepinephrine increased ARNA 1,870 [+ or -] 210%'s. Immunohistochemical studies showed that the sympathetic and sensory nerves were closely related in the pelvic wall. Renal pelvic perfusion with prazosin blocked and rauwolscine enhanced the ARNA responses to reflex increases in ERSNA and norepinephrine. Studies in a denervated renal pelvic wall preparation showed that norepinephrine increased substance P release, from 8 [+ or -] 1 to 16 [+ or -] 1 pg/min, and [PGE.sub.2] release, from 77 [+ or -] 11 to 161 [+ or -] 23 pg/min, suggesting a role for [PGE.sub.2] in the norepinephrine-induced activation of renal sensory nerves. Prazosin and indomethacin reduced and rauwolscine enhanced the norepinephrine-induced increases in substance P and [PGE.sub.2]. [PGE.sub.2] enhanced the norepinephrine-induced activation of renal sensory nerves by stimulation of EP4 receptors. Interaction between ERSNA and ARNA is modulated by norepinephrine, which increases and decreases the activation of the renal sensory nerves by stimulating [[alpha].sub.1]- and [[alpha].sub.2]-adrenoceptors, respectively, on the renal pelvic sensory nerve fibers. Norepinephrine-induced activation of the sensory nerves is dependent on renal pelvic synthesis/release of [PGE.sub.2]. substance P; EP4 receptor; pelvis; prazosin; rauwolscine

Research during the past two decades supports a complex role for neuropeptide tyrosine (NPY) and two of its associated receptors, the [Y.sub.1] receptor and the [Y.sub.2] receptor, in the modulation of pain, in addition to regeneration and survival mechanisms at the spinal level. Thus, NPY has been shown to both cause and reduce pin, in addition to having biphasic effects. Recent research has focused on the distribution of the spinal NPY-mediated system. Here, we propose various possible scenarios for the role of NPY in pain processing, based on its actions at different sites (axon versus cell body), through different receptors ([Y.sub.1] receptor versus [Y.sub.2] receptor) and/or types of neuron (ganglion neurons and intraganglionic cross-excitation versus interneurons versus projection neurons).

Autoimmune polyendocrine syndrome type 1 (APS1) is a rare autosomal recessive disorder caused by mutations in the autoimmune regulator (AIRE) gene, High titer autoantibodies (Aabs) toward intracellular enzymes are a hallmark for APS1 and serve as diagnostic markers and predictors for disease manifestations, in this study, we aimed to identify pituitary autoantigens in patients with APS1. A pituitary cDNA expression library was screened with APS1 sera and a tudor domain containing protein 6 (TDRD6) cDNA clone was isolated. Positive immunoreactivity against in vitro translated TDRD6 fragments was shown in 42/86 (49%) APS1 patients but not in patients with other autoimmune diseases or in healthy controls. By using immunohistochemistry, sera from 3/6 APS1 patients with growth hormone (GH) deficiency showed immunostaining of a small number of guinea pig anterior pituitary cells, and 40-50% of these cells were GH-positive. No such immunostaining was seen with sera from healthy controls. The APS1 Aab-positive, GH-negative cells may represent a novel subpopulation of anterior pituitary cells. In addition, 4/6 patient sera showed staining of a fiber-plexus in the pituitary intermediate lobe recognizing enzymes of monoamine and GABA synthesis. Thus, we have identified TDRD6 as a major autoantigen in APS1 patients and shown that several sera from GH-deficient patients stain specific cell populations and nerves in the pituitary gland. autoantigens | growth hormone deficiency | pituitary intermediate lobe | tudor domain containing protein 6

Author(s): Milan Chromek [1]; Zuzana Slamová [1]; Peter Bergman [2]; László Kovács [3]; L'udmila Podracká [4]; Ingrid Ehrén [5]; Tomas Hökfelt [6]; Gudmundur H Gudmundsson [7]; Richard L Gallo [8]; [...]

The neuropeptide galanin mediates its effects through the receptor subtypes [Gal.sub.1], [Gal.sub.2], and [Gal.sub.3] and has been implicated in anxietyand depression-related behaviors. Nevertheless, the receptor subtypes relevant to these behaviors are not known because of the lack of available galanin-selective ligands. In this article, we use behavioral, neurochemical, and electrophysiological approaches to investigate the anxiolytic- and antidepressant-like effects of two potent small-molecule, [Gal.sub.3]-selective antagonists, SNAP 37889 and the more soluble analog SNAP 398299. Acute administration of SNAP 37889 or SNAP 398299 enhanced rat social interaction. Furthermore, acute SNAP 37889 was also shown to reduce guinea pig vocalizations after maternal separation, to attenuate stress-induced hyperthermia in mice, to increase punished drinking in rats, and to decrease immobility and increase swimming time during forced swim tests with rats. Moreover, SNAP 37889 increased the social interaction time after 14 days of treatment and maintained its antidepressant effects during forced swim tests with rats after 21 days of treatment. In microdialysis studies, SNAP 37889 partially antagonized the galanin-evoked reduction in hippocampal serotonin (5-hydroxytryptamine, 5-HT), as did the 5-H[T.sub.1A] receptor antagonist WAY100635. Their combination produced a complete reversal of the effect of galanin. SNAP 398299 partially reversed the galanin-evoked inhibition of dorsal raphe cell firing and galanin-evoked hyperpolarizing currents. These results indicate that [Gal.sub.3]-selective antagonists produce anxiolytic- and antidepressant-like effects, possibly by attenuating the inhibitory influence of galanin on 5-HT transmission at the level of the dorsal raphe nucleus. anxiety | depression | galanin | neuropeptide | dorsal raphe

Previously, we identified that a majority of patients with anorexia nervosa (AN) and bulimia nervosa (BN) as well as some control subjects display autoantibodies (autoAbs) reacting with [alpha]-melanocyte-stimulating hormone ([alpha]-MSH) or adrenocorticotropic hormone, melanocortin peptides involved in appetite control and the stress response. In this work, we studied the relevance of such autoAbs to AN and BN. In addition to previously identified neuropeptide autoAbs, the current study revealed the presence of autoAbs reacting with oxytocin (OT) or vasopressin (VP) in both patients and controls. Analysis of serum levels of identified autoAbs showed an increase of IgM autoAbs against [alpha]-MSH, OT, and VP as well as of IgG autoAbs against VP in AN patients when compared with BN patients and controls. Further, we investigated whether levels of these autoAbs correlated with psychological traits characteristic for eating disorders. We found significantly altered correlations between [alpha]-MSH autoAb levels and the total Eating Disorder Inventory-2 score, as well as most of its subscale dimensions in AN and BN patients vs. controls. Remarkably, these correlations were opposite in AN vs. BN patients. In contrast, levels of autoAbs reacting with adrenocorticotropic hormone, OT, or VP had only few altered correlations with the Eating Disorder Inventory-2 subscale dimensions in AN and BN patients. Thus, our data reveal that core psychobehavioral abnormalities characteristic for eating disorders correlate with the levels of autoAbs against [alpha]-MSH, suggesting that AN and BN may be associated with autoAb-mediated dysfunctions of primarily the melanocortin system. anorexia | autoimmunity | behavior | bulimia | hypothalamus

Recently, MHC class I molecules have been shown to be important for the retraction of synaptic connections that normally occurs during development [Huh, G.S., Boulanger, L. M., Du, H., Riquelme, P. A., Brotz, T. M. & Shatz, C. J. (2000) Science 290, 2155-2158]. In the adult CNS, a classical response of neurons to axon lesion is the detachment of synapses from the cell body and dendrites. We have investigated whether MHC I molecules are involved also in this type of synaptic detachment by studying the synaptic input to sciatic motoneurons at I week after peripheral nerve transection in [beta]-microglobulin or transporter associated with antigen processing 1-null mutant mice, in which cell surface MHC I expression is impaired. Surprisingly, lesioned motoneurons in mutant mice showed more extensive synaptic detachments than those in wild-type animals. This surplus removal of synapses was entirely directed toward inhibitory synapses assembled in clusters. In parallel, a significantly smaller population of motoneurons reinnervated the distal stump of the transected sciatic nerve in mutants. MHC I molecules, which traditionally have been linked with immunological mechanisms, are thus crucial for a selective maintenance of synapses during the synaptic removal process in neurons after lesion, and the lack of MHC I expression may impede the ability of neurons to regenerate axons. [beta]2-microglobulin | motoneuron | spinal cord | synapse elimination | nerve lesion

Induction of cyclooxygenase-2 (COX-2) in the renal pelvic wall increases prostaglandin E2 (PG[E.sub.2]) leading to stimulation of cAMP production, which results in substance P (SP) release and activation of renal mechanosensory nerves. The subtype of PGE receptors involved, EP2 and/or EP4, was studied by immunohistochemistry and renal pelvic administration of agonists and antagonists of EP2 and EP4 receptors. EP4 receptor-like immunoreactivity (LI) was colocalized with calcitonin gene-related peptide (CGRP)-LI in dorsal root ganglia (DRGs) at [Th.sub.9]-[L.sub.1] and in nerve terminals in the renal pelvic wall. [Th.sub.9]-[L.sub.1] DRG neurons also contained EP3 receptor-LI and COX-2-LI, each of which was colocalized with CGRP-LI in some neurons. No renal pelvic nerves contained EP3 receptor-LI and only very few nerves COX-2-LI. The EPI/EP2 receptor antagonist AH-6809 (20 [micro]M) had no effect on SP release produced by PGE2 (0.14 [micro]M) from an isolated rat renal pelvic wall preparation. However, the EP4 receptor antagonist L-161,982 (10 [micro]M) blocked the SP release produced by the EP2/EP4 receptor agonist butaprost (10 [micro]M) 12 [+ or -] 2 vs. 2 [+ or -] 1 and PG[E.sub.2], 9 [+ or -] 1 vs. 1 [+ or -] 0 pg/min. The SP release by butaprost and PGE2 was similarly blocked by the EP4 receptor antagonist AH-23848 (30 [micro]M). In anesthetized rats, the afferent renal nerve activity (ARNA) responses to butaprost 700 [+ or -] 100 and PGE2 x 780 [+ or -] 100% x s (area under the curve of ARNA vs. time) were unaffected by renal pelvic perfusion with AH-6809. However, 1 [micro]M L-161,982 and 10 [micro]M AH-23848 blocked the ARNA responses to butaprost by 94 [+ or -] 5 and 78 [+ or -] 10%, respectively, and to PGE2 by 74 [+ or -] 16 and 74 [+ or -] 11%, respectively. L-161,982 also blocked the ARNA response to increasing renal pelvic pressure 10 mmHg, 85 [+ or -] 5%. In conclusion, PG[E.sub.2] increases renal pelvic release of SP and ARNA by activating EP4 receptors on renal sensory nerve fibers. EP3 receptors; cyclooxygenase-2; substance P; butaprost; L-161,982

Trafficking of the galanin R2 receptor (GALR2) fused with enhanced GFP (EGFP) was studied by using confocal fluorescence microscopy. The fusion protein was predominantly localized on the plasma membrane with some intracellular fluorescent structures (vesicles), mainly in the perinuclear region. Incubation with galanin resulted in a concentration-dependent increase in intracellular [Ca.sup.2+] concentration levels, suggesting that the GALR2-EGFP conjugate is functional. After blocking endocytosis with methyl-[beta]cyclodextrin GALR2-EGFP expression was increased on the surface and decreased in the cytoplasm. Blocking endocytic recycling with monensin caused an increase of intracellular GALR2-EGFP accumulation and a decrease of fluorescence on the plasma membrane. GALR2-EGFP on the plasma membrane was internalized within 5-10 min after treatment with galanin or AR-M1896, a selective GALR2 agonist, with a dramatic reduction in plasma membrane localization and appearance in intracellular vesicles. Neither M35 nor M40, two galanin analogues with putative antagonistic action, prevented GALR2 agonist-induced internalization of GALR2-EGFP, suggesting that they are not antagonists at this receptor under the present circumstances. Galanin stimulation at low temperature caused GALR2-EGFP aggregation and clustering on the surface but no translocation to cytoplasm. After coincubation with galanin the GALR2-EGFP was colocalized with internalized Texas red-transferrin, a marker of the clathrin endocytic pathway. Hyperosmotic sucrose inhibited internalization of GALR2-EGFP. Taken together these findings indicate that GALR2 undergoes constitutive endocytosis and recycling and that both ligand-independent and ligand-dependent internalization use the clathrin-dependent endocytic recycling pathway.

Basal and forced swimming (FS) stress-induced release of nor-adrenaline (NA) and serotonin (5-HT) were determined by in vivo microdialysis in the ventral hippocampus of mice overexpressing galanin under the platelet-derived growth factor B promoter (GaIOE/P) or under the dopamine [beta]-hydroxylase promoter (GaIOE/D) (only NA). WT mice served as controls. Intraventricular infusion of galanin significantly reduced basal extracellular NA in WT mice and in GalOE/P mice (albeit less so). Microdialysis sampling during a 10-min FS showed that NA and 5-HT release were elevated to 213% and 156%, respectively, in the GalOE/P group, whereas in the WT group the increases were only 127% and 119%, respectively. The second (repeated) 10-min FS (RFS) caused a marked enhancement of NA and 5-HT release in the GalOE/P mice to 344% and 275%, respectively. However, the RFS caused only a 192% increase of extracellular NA levels in the GalOE/D mice. Pretreatment with the putative peptidergic galanin receptor antagonist M35 almost completely blocked the elevation of NA and 5-HT levels in the GalOE/P after RFS. These results suggest that the NA and 5-HT hippocampal afferents in GalOE/P mice are hypersensitive to both conditioned and unconditioned stressful stimuli, such as FS, and that this effect is mediated by galanin receptors. The present findings support a role of galanin in the regulation of release of NA and 5-HT, two neurotransmitters involved in mood control. microdialysis | 5-hydroxytryptamine | transgenic mice | hippocampus | affective disorders