Regulation of nitric oxide synthase messenger RNA expression in the rat hippocampus by glucocorticoids

Nitric oxide and glucocorticoids have been implicated in learning and memory, as well as in regulation of the stress response. By use of the in situ hybridization technique, we examined the role of glucocorticoids in the regulation of nitric oxide synthase messenger RNA in the hippocampus. In contro...

Full description

Saved in:
Bibliographic Details
Published in:Neuroscience 1998-11, Vol.87 (2), p.439-446
Main Authors: López-Figueroa, M.O, Itoi, K, Watson, S.J
Format: Article
Language:English
Subjects:
Adrenalectomy
Animals
Anti-Inflammatory Agents - pharmacology
Biochemistry and metabolism
Biological and medical sciences
Central nervous system
Corticosterone - pharmacology
Dexamethasone - pharmacology
Fundamental and applied biological sciences. Psychology
Glucocorticoids - physiology
hippocampus
Hippocampus - metabolism
Image Processing, Computer-Assisted
In Situ Hybridization
Male
nitric oxide synthase
Nitric Oxide Synthase - biosynthesis
Nitric Oxide Synthase Type I
Pyramidal Cells - enzymology
pyramidal neurons
Rats
Rats, Sprague-Dawley
RNA, Messenger - biosynthesis
steroids
Vertebrates: nervous system and sense organs
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Nitric oxide and glucocorticoids have been implicated in learning and memory, as well as in regulation of the stress response. By use of the in situ hybridization technique, we examined the role of glucocorticoids in the regulation of nitric oxide synthase messenger RNA in the hippocampus. In control animals, nitric oxide synthase subtype I (neuronal) messenger RNA was expressed in the CA1, CA3 and dentate gyrus of the hippocampus. Nitric oxide synthase subtype I expression was almost absent in CA2 pyramidal neurons. Neither subtype II (immunological) nor subtype III (endothelial) nitric oxide synthase messenger RNAs were observed in neurons of the hippocampal subfields. Bilateral removal of the adrenal glands resulted in a significant increase in nitric oxide synthase subtype I messenger RNA expression in the CA1 and CA3 pyramidal neurons and in granular cells of the dentate gyrus. To a lesser degree, the nitric oxide synthase subtype I messenger RNA signal was increased in CA2 pyramidal neurons. Daily administration of glucocorticoids for one week attenuated the adrenalectomy-induced increased level of expression of the messenger RNA encoding nitric oxide synthase subtype I in all areas studied. Because adrenalectomy, which suppresses the production of glucocorticoids, increases nitric oxide synthase expression, and replacement of adrenalectomized animals with glucocorticoids restores the basal levels of nitric oxide synthase subtype I expression, our results demonstrate an up-regulation of nitric oxide synthase subtype I messenger RNA in the absence of glucocorticoids in the hippocampus. The present findings suggest an involvement of the stress axis in the regulation of the synaptic plasticity process mediated by nitric oxide in the hippocampus.
ISSN:0306-4522
1873-7544
DOI:10.1016/S0306-4522(98)00075-X