TY - JOUR AB - Dorsal raphe nucleus (DRN) neurons are reciprocally connected to the locus coeruleus (LC) and send neural pathways to the medial hypothalamus (MH). The aim of this work was to investigate whether the blockade of alpha(1)-, alpha(2)- or beta-noradrenergic receptors in the DRN or the inactivation of noradrenergic neurons in the LC modify defensive behaviours organised by MH neurons. For this purpose, Wistar male rats received microinjections of WB4101, RX821002, propranolol (alpha(1)-, alpha(2)- and beta-noradrenergic receptor antagonists, respectively) or physiological saline in the DRN, followed 10 min later by MH GABA(A) receptor blockade. Other groups of animals received DSP-4 (a noradrenergic neurotoxin), physiological saline or only a needle insertion (sham group) into the LC, and 5 days later, bicuculline or physiological saline was administered in the MH. In all these cases, after MH treatment, the frequency and duration of defensive responses were recorded over 15 min. An anterograde neural tract tracer was also deposited in the DRN. DRN neurons send pathways to lateral and dorsomedial hypothalamus. Blockade of alpha(1)- and beta-noradrenergic receptors in the DRN decreased escape reactions elicited by bicuculline microinjections in the MH. In addition, a significant increase in anxiety-like behaviours was observed after the blockade of alpha(2)-noradrenergic receptors in the DRN. LC pretreatment with DSP-4 decreased both anxiety- and panic attack-like behaviours evoked by GABA(A) receptor blockade in the MH. In summary, the present findings suggest that the norepinephrine-mediated system modulates defensive reactions organised by MH neurons at least in part via noradrenergic receptors recruitment on DRN neurons. AU - Uribe-Mariño, A.* AU - Castiblanco-Urbina, M.A. AU - Falconi-Sobrinho, L.L.* AU - dos Anjos-Garcia, T.* AU - de Oliveira, R.C.* AU - Mendes-Gomes, J.* AU - da Silva Soares, R.* AU - Matthiesen, M.* AU - Almada, R.C.* AU - De Oliveira, R.* AU - Coimbra, N.C.* C1 - 57038 C2 - 47479 CY - Radarweg 29, 1043 Nx Amsterdam, Netherlands TI - The alpha- and beta-noradrenergic receptors blockade in the dorsal raphe nucleus impairs the panic-like response elaborated by medial hypothalamus neurons. JO - Brain Res. VL - 1725 PB - Elsevier PY - 2019 SN - 0006-8993 ER - TY - JOUR AB - In the central nervous system, NG2-glia are the cells responsible for the generation of mature oligodendrocytes during development and adulthood. Some studies could show that NG2-glia can give origin also to astrocytes and neurons, a property that makes them similar to neural stem cells. Beside their important role as progenitors, NG2-glia are believed also to have more functions due to their unique interaction with neurons through synapses. It is however not clear whether these features are common to all NG2-glia or different subpopulations of NG2-glia devoted to different functions exist. Therefore the aim of this review is to highlight the state of the art on NG2-glia heterogeneity from development to adulthood and in different brain areas, and discuss the impact of it on our understanding of the glial neurobiology. This article is part of a Special Issue entitled SI:NG2-glia(Invited only). AU - Viganò, F.* AU - Dimou, L. C1 - 47219 C2 - 40531 CY - Amsterdam SP - 129-137 TI - The heterogeneous nature of NG2-glia. JO - Brain Res. VL - 1638 PB - Elsevier Science Bv PY - 2016 SN - 0006-8993 ER - TY - JOUR AB - The subependymal zone at the lateral ventricular wall represents a major neurogenic niche of the adult mammalian brain and continuously provides new neurons for the olfactory bulb. A mosaic of stem and progenitor cells in this niche has the potential to respond to multiple signals including growth factors such as EGF. Recent studies using long-term ventricular infusion of EGF demonstrate intense cell proliferation around the ventricular wall, implicating the presence of EGF-reactive cells also outside the classical neurogenic lateral niche. Here we show that intraventricular injection of EGF induces within minutes CREB and ERK phosphorylation in astrocyte-like progenitor cells (type B cells) and EGF receptor-expressing transit-amplifying progenitor cells-both in the striatal and septal ventricular walls. EGF infusion for 6 days induced continued CREB and ERK activation in nestin+ cells paralleled by intense periventricular cell proliferation. In addition, the ependyma became EGF receptor-immunoreactive, revealed intense CREB phosphorylation and underwent partial de-differentiation. Our results demonstrate that intraventricular application of EGF induces CREB and ERK phosphorylation along the entire ventricular walls and thus permits a direct identification of EGF-responsive cell types. They further support the notion that not only the striatal ventricular wall where the SEZ is located but also the septal ventricular wall carries latent potential for the formation of neurons and glial cells. AU - Gampe, K.* AU - Brill, M.S. AU - Momma, S.* AU - Götz, M. AU - Zimmermann, H.* C1 - 6290 C2 - 28336 SP - 31-41 TI - EGF induces CREB and ERK activation at the wall of the mouse lateral ventricles. JO - Brain Res. VL - 1376 PB - Elsevier PY - 2011 SN - 0006-8993 ER - TY - JOUR AB - The function and regulation of the hypothalamic-pituitary-adrenal (HPA) axis during ontogeny differs markedly from the situation in adult animals. Postnatally mice undergo a so-called stress hypo-responsive period, which is characterized by a relative inability of mild stressors to induce a marked corticosterone response. Steroid receptor coactivators (SRCs) have been shown to influence the function of the HPA axis in adult animals by interacting with steroid receptors as the mineralocorticoid and the glucocorticoid receptor. Here we test the hypothesis that expression changes of the three identified SRC genes (SRC1, SRC2 and SRC3) correlate with differences in HPA axis activity during postnatal development. First, we mapped the ontogeny of the three SRCs during postnatal development in the hippocampus. We found a time- and region-specific regulation of gene expression, which was specific for each SRC. However, there was no relation between the age-dependent stress system activity and the expression levels of the SRCs. Further, we studied the acute regulation of the three SRCs following maternal deprivation in 9-day-old wild-type or CRH receptor type 1 (CRHr1) knockout mice. Under these conditions, no differential expression of any of the tested SRCs could be detected. Thus, while it seems likely that their varying abundance throughout postnatal life affects steroid receptor function in the different hippocampal subregions, acute changes of HPA axis activity or reactivity are not mediated by hippocampal changes in expression of this coactivator family. AU - Schmidt, M.V.* AU - Oitzl, M.* AU - Steenbergen, P.* AU - Lachize, S.* AU - Wurst, W. AU - Müller, M.B. AU - de Kloet, E.R. AU - Meijer, O.C. C1 - 644 C2 - 24858 SP - 1-6 TI - Ontogeny of steroid receptor coactivators in the hippocampus and their role in regulating postnatal HPA axis function. JO - Brain Res. VL - 1174 IS - 1 PB - Elsevier PY - 2007 SN - 0006-8993 ER - TY - JOUR AB - Several studies have demonstrated in the past that endogenous opioid peptides and opioid receptors may be involved as mediators of brain tissue growth and function in the neonate. Applying histological and autoradiographic methods, we have examined the effect of the μ-receptor-specific antagonist, naltrexone, on the proliferation of the 4–12-week-old rat forebrain subependymal layer. We found that naltrexone, when given daily throughout the weaning period, evoked a long-lasting increase of the mitotic rate and the [3H]thymidine labelling index. This effect was most significant about 8–10 weeks after ending the naltrexone treatment. Although a direct influence of naltrexone on long-term subependymal cell proliferation cannot be excluded, we are discussing evidence of an indirect effect via suppression of noradrenergic activity in the forebrain. AU - Schmahl, W. AU - Funk, R. AU - Miaskowski, U. AU - Plendl, J. C1 - 17764 C2 - 10671 SP - 297-300 TI - Long-lasting Effects of Naltrexone, an Opioid Receptor Antagonist, on Cell Proliferation in Developing Rat Forebrain. JO - Brain Res. VL - 486 IS - 2 PY - 1989 SN - 0006-8993 ER - TY - JOUR AB - Several studies have demonstrated in the past that endogenous opioid peptides and opioid receptors may be involved as mediators of brain tissue growth and function in the neonate. Applying histological and autoradiographic methods, we have examined the effect of the μ-receptor-specific antagonist, naltrexone, on the proliferation of the 4-12-week-old rat forebrain subependymal layer. We found that naltrexone, when given daily throughout the weaning period, evoked a long-lasting increase of the mitotic rate and the [3H]thymidine labelling index. This effect was most significant about 8-10 weeks after ending the naltrexone treatment. Although a direct influence of naltrexone on long-term subependymal cell proliferation cannot be excluded, we are discussing evidence of an indirect effect via suppression of noradrenergic activity in the forebrain. AU - Schmahl, W.G. AU - Funk, R.C. AU - Miaskowski, U. AU - Plendl, J. C1 - 42063 C2 - 36488 SP - 297-300 TI - Long-lasting effects of naltrexone, an opioid receptor antagonist, on cell proliferation in developing rat forebrain. JO - Brain Res. VL - 486 IS - 2 PY - 1989 SN - 0006-8993 ER -