0
views
0
recommends
+1 Recommend
1 collections
    0
    shares
      • Record: found
      • Abstract: found
      • Article: found

      Central 5-Hydroxytryptamine-2A Receptor Expression in Transgenic Mice Bearing a Glucocorticoid Receptor Antisense

      Read this article at

      ScienceOpenPublisherPubMed
      Bookmark
          There is no author summary for this article yet. Authors can add summaries to their articles on ScienceOpen to make them more accessible to a non-specialist audience.

          Abstract

          Transgenic mice bearing a transgene coding for a glucocorticoid receptor antisense mRNA that partially blocks glucocorticoid receptor expression were used to investigate the long-term effect of hypothalamic-pituitary-adrenal dysfunction on brain 5-hydroxytryptamine-2A (5-HT<sub>2A</sub>) receptor expression. The brain 5-HT<sub>2A</sub> receptor mRNA levels in transgenic mice were measured by in situ hybridization and compared to those in control mice. We also studied the effect of a 3-week treatment with fluoxetine on brain 5-HT<sub>2A</sub> receptor expression in the transgenic mice. No difference in 5-HT<sub>2A</sub> mRNA levels was observed between transgenic and control mice in cortical or striatal regions, and fluoxetine treatment was without effect. No difference in hypothalamic 5-HT<sub>2A</sub> mRNA levels was observed between transgenic and control mice, while fluoxetine treatment increased these levels in both transgenic as well as in the hypothalamic ventromedial and paraventricular nuclei of control mice. 5-HT<sub>2A</sub> receptor mRNA levels were similar in hippocampal CA1 and CA2 subregions of control and transgenic, but were lower in the CA3 and CA4 subregions of transgenic mice. Fluoxetine had no effect on 5-HT<sub>2A</sub> mRNA levels of transgenic mice but reduced control mouse 5-HT<sub>2A</sub> receptor mRNA levels in the CA3 subregion. These results suggest that impaired glucocorticoid receptor function can affect hippocampal 5-HT<sub>2A</sub> receptor expression in transgenic mice and that this is not corrected by fluoxetine treatment.

          Related collections

          Most cited references 18

          • Record: found
          • Abstract: found
          • Article: not found

          The antidepressants fluoxetine, idazoxan and phenelzine alter corticotropin-releasing hormone and tyrosine hydroxylase mRNA levels in rat brain: therapeutic implications.

          Various classes of antidepressant drugs with distinct pharmacologic actions are differentially effective in the treatment of classic melancholic depression--characterized by pathological hyperarousal and atypical depression--associated with lethargy, hypersomnia, and hyperphagia. All antidepressant agents exert their therapeutic efficacy only after prolonged administration. In situ hybridization histochemistry was used to examine in rats the effects of short-term (2 weeks) and long-term (8 weeks) administration of 3 different classes of activating antidepressant drugs which tend to be preferentially effective in treating atypical depressions, on the expression of central nervous system genes thought to be dysregulated in major depression. Daily administration (5 mg/kg, i.p.) of the selective 5-hydroxytryptophan (5-HT) reuptake inhibitor fluoxetine, the selective alpha 2-adrenergic receptor antagonist idazoxan, and the nonspecific monoamine oxidase A and B inhibitor phenelzine increased tyrosine hydroxylase mRNA levels by 70-150% in the locus coeruleus after 2 weeks of drug and by 71-115% after 8 weeks. The 3 drugs decreased corticotropin-releasing hormone mRNA levels by 30-48% in the paraventricular nucleus of the hypothalamus. The decreases occurred at 8 weeks but not at 2 weeks. No consistent change in steroid hormone receptor mRNA levels was seen in the hippocampus with the 3 drugs, but fluoxetine and idazoxan increased the level of mineralocorticoid receptor (MR) and glucocorticoid receptor (GR) mRNA, respectively, after 8 weeks of drug administration. Proopiomelanocortin (POMC) mRNA levels in the anterior pituitary and plasma adrenocorticotropic-hormone (ACTH) levels were not altered after 2 or 8 weeks of drug treatment.(ABSTRACT TRUNCATED AT 250 WORDS)
            Bookmark
            • Record: found
            • Abstract: not found
            • Article: not found

            Physiopharmacological interactions between stress hormones and central serotonergic systems

              Bookmark
              • Record: found
              • Abstract: found
              • Article: not found

              Impaired type II glucocorticoid-receptor function in mice bearing antisense RNA transgene.

              Glucocorticoids, in conjunction with their cognate receptors, exert negative-feedback effects on the hypothalamus-pituitary-adrenal axis, suppressing adrenal steroid secretions. Two types of corticosteroid receptor, distinguishable by their ability to bind corticosterone, have been identified as classical mineralocorticoid (type I) and glucocorticoid (type II) receptors by cloning their complementary DNAs. The type I receptor controls the basal circadian rhythm of corticosteroid secretion. Both receptor types are involved in negative feedback, but the type II receptor may be more important for terminating the stress response as it is the only one to be increased in animals rendered more sensitive to corticosteroid negative-feedback effects. Here we create a transgenic mouse with impaired corticosteroid-receptor function by partially knocking out gene expression with type II glucocorticoid receptor antisense RNA. We use this animal to study the glucocorticoid feedback effect on the hypothalamus-pituitary-adrenal axis.
                Bookmark

                Author and article information

                Journal
                NEN
                Neuroendocrinology
                10.1159/issn.0028-3835
                Neuroendocrinology
                S. Karger AG
                0028-3835
                1423-0194
                2001
                January 2001
                30 January 2001
                : 73
                : 1
                : 37-45
                Affiliations
                aOncology and Molecular Endocrinology Research Center and bNeuroscience Laboratory, CHUQ, Pavillon CHUL, Laval University, Sainte-Foy, and cDepartment of Psychiatry, Douglas Hospital Research Center, McGill University, Verdun, Canada
                Article
                54618 Neuroendocrinology 2001;73:37–45
                10.1159/000054618
                11174015
                © 2001 S. Karger AG, Basel

                Copyright: All rights reserved. No part of this publication may be translated into other languages, reproduced or utilized in any form or by any means, electronic or mechanical, including photocopying, recording, microcopying, or by any information storage and retrieval system, without permission in writing from the publisher. Drug Dosage: The authors and the publisher have exerted every effort to ensure that drug selection and dosage set forth in this text are in accord with current recommendations and practice at the time of publication. However, in view of ongoing research, changes in government regulations, and the constant flow of information relating to drug therapy and drug reactions, the reader is urged to check the package insert for each drug for any changes in indications and dosage and for added warnings and precautions. This is particularly important when the recommended agent is a new and/or infrequently employed drug. Disclaimer: The statements, opinions and data contained in this publication are solely those of the individual authors and contributors and not of the publishers and the editor(s). The appearance of advertisements or/and product references in the publication is not a warranty, endorsement, or approval of the products or services advertised or of their effectiveness, quality or safety. The publisher and the editor(s) disclaim responsibility for any injury to persons or property resulting from any ideas, methods, instructions or products referred to in the content or advertisements.

                Page count
                Figures: 3, Tables: 1, References: 67, Pages: 9
                Categories
                Neuroendocrine Regulation of Brain Receptor Expression

                Comments

                Comment on this article