Linked Life Data

954641

Source:http://linkedlifedata.com/resource/pubmed/id/954641

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2
pubmed:dateCreated
1976-11-1
pubmed:abstractText
The effects of intraventricular norepinephrine (NE) and dopamine (DA) were studied in the awake, freely behaving rat. In long-term ovariectomized, estrogen-progesterone-primed (OVE E2-P) animals, blood samples were taken via indwelling intra-atrial catheters before and after intraventricular infusion of either pH-adjusted saline, NE )5 mug, 15 mug, 20 mug), or DA (4 mug, 15 mug), and plasma LH was measured by radioimmunoassay. Under urethane anesthesia, records were made of the effects of intraventricular saline and NE on the electrical activity of the arcuate nucleus in the form of multi-unit spike activity. In unanesthetized animals, intraventricular NE caused marked changes in behavior. The typical response consisted of three phases: generalized activation (5-7 min), feeding (5-15 min), and sleep 1-2 h). DA exerted similar behavioral effects but without the marked sleep phase characteristic of the NE response. The effects of the catecholamines on LH output were significant increases in plasma LH levels for all NE doses tested (5 mug, p less than .025; 15 mug, p less than .05; 20 mug, p less than .005), while DA had no effect. The dynamics of the LH response to NEwere similar at all dosage levels, and the increase caused by 20 mug NE was found to be essentially equal to that induced by a quick intravenous infusion of 1.25 ng LHRH. Arcuate nucleus multi-unit spike activity (MUSA) showed a clear response to intraventricular NE at a dosage capable of stimulating the release of LH. In every case, the initial effect was a decrease in spike activity. These results, considered in relation to previous findings, suggest that NE may be stimulatory to neurons secreting LH-releasing hormone (LHRH). The decrease in arcuate nucleus MUSA in response to NE implies that certain elements of this nucleus are inhibited during LH release, perhaps the dopaminergic tuberoinfundibular neurons.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
AIM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Aug
pubmed:issn
0013-7227
pubmed:author
pubmed:issnType
Print
pubmed:volume
99
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
411-9
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1976
pubmed:articleTitle
Effects of intraventricular catecholamines on luteinizing hormone release in ovariectomized-steroid-primed rats.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S.