Linked Life Data

1986985

Source:http://linkedlifedata.com/resource/pubmed/id/1986985

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
1991-2-19
pubmed:abstractText
To examine whether baroreceptor reflex regulation by the posterior hypothalamus becomes modified with age, we compared baroreceptor reflex sensitivity and hypothalamic responsiveness in 2- and 10-month-old rats anesthetized with urethane-chloralose. Hypothalamic regulation of baroreceptor reflex sensitivity was assessed by recording responses to intravenously infused phenylephrine and afferent aortic nerve stimulation after sham operation or electrolytic destruction of the posterior hypothalamus. Regardless of age, reflex bradycardia and sympathoinhibition elicited during pressor responses to phenylephrine, as well as all cardiovascular and sympathetic nerve responses to afferent aortic nerve stimulation, were stronger in rats with bilateral hypothalamic lesions than in age-matched, sham-operated controls. Distinctively, because baroreceptor reflex sensitivity differed with age only in sham-operated controls but not in lesioned rats, we concluded that age-related differences in baroreceptor reflex sensitivity had been abolished by posterior hypothalamic lesions. Other experiments were then performed to compare responses to graded electrical stimulation of the posterior hypothalamus in baroreceptor-intact rats. Pressor and sympathoexcitatory responses to hypothalamic stimulation were larger, and stimulus thresholds were lower at 10 than at 2 months of age thereby suggesting that hypothalamic responsiveness had increased with age. Our results are in accord with the interpretation that aging exacerbates the baroreceptor reflex suppression normally exerted by the posterior hypothalamus.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jan
pubmed:issn
0194-911X
pubmed:author
pubmed:issnType
Print
pubmed:volume
17
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
80-90
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
1991
pubmed:articleTitle
Aging escalates baroreceptor reflex suppression by the posterior hypothalamus in rats.
pubmed:affiliation
Department of Pharmacology, College of Health Sciences and Hospital, University of Kansas Medical Center, Kansas City 66103.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't