Linked Life Data

7606489

Source:http://linkedlifedata.com/resource/pubmed/id/7606489

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2
pubmed:dateCreated
1995-8-15
pubmed:abstractText
Two experiments were carried out in the albino rat to investigate the role of brain adrenergic systems in DNA remodeling. Adult male Sprague-Dawley rats were given an intraventricular microinjection of an adrenergic drug or vehicle followed 2 h later by the intraventricular injection of 50 microCi of [3H-methyl]thymidine. The rats were sacrificed 0.5 h after the injection of the radioactive tracer. The rate of DNA synthesis was determined by measuring the amount of radioactive precursor incorporated into the DNA extracted from homogenates of several brain areas. In Experiment 1, at time 0 rats received the alpha-adrenergic antagonist phentolamine (5 micrograms), the beta antagonist propranolol (10 micrograms), the alpha agonist phenylephrine (1 microgram), the beta agonist isoproterenol (12.5 micrograms), or the vehicle. The latter decreased UBDS in neocortex, and increased it in the septum, neostriatum, hypothalamus, cerebellum, and rest of the brain. The alpha and beta agonists and antagonists induced several significant effects, depending on the brain region. In Experiment 2, rats were bilaterally lesioned in the dorsal noradrenergic bundle (DNB) by injection of 6-hydroxydopamine or were sham lesioned. One week later, at time 0 they were given the alpha agonist phenylephrine (1 microgram), the beta agonist isoproterenol (12.5 micrograms), or the vehicle. The DNB-lesioned rats showed a higher UBDS in the hippocampus, neocortex, and hypothalamus, which was reversed by the alpha or the beta agonist. The results suggest an influence of the DNB, probably as a tonic inhibitor of UBDS in the hippocampus and the hypothalamus which, in turn, are likely to be mediated by beta- and alpha-adrenergic receptors. In addition, a phasic inhibitory effect seems to be mediated by beta and alpha receptors in the neocortex, and by beta receptors in the cerebellum. A modulatory role of central adrenergic systems on unscheduled brain DNA synthesis may be inferred from these findings.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:issn
0361-9230
pubmed:author
pubmed:issnType
Print
pubmed:volume
37
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
139-48
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1995
pubmed:articleTitle
Adrenergic receptor systems and unscheduled DNA synthesis in the rat brain.
pubmed:affiliation
Department of Human Physiology, F. Bottazzi, Second University of Naples (SUN), Italy.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't