Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
4
pubmed:dateCreated
2002-10-4
pubmed:abstractText
We compared the electrophysiological properties of neurons in the rostral ventrolateral medulla (RVLM) of neonatal Wistar-Kyoto rats (WKY) and spontaneously hypertensive rats (SHR), and responses to angiotensin II and its type 1 receptor antagonist candesartan. Using the whole-cell patch-clamp technique, we examined the characteristics of RVLM neurons in brainstem-spinal cord preparations with a preserved sympathetic neuronal network. The baseline membrane potential of irregularly firing neurons was less negative (-50.1+/-0.6 versus -52.0+/-0.6 mV) and the firing rate was faster (3.0+/-0.2 versus 2.0+/-0.2 Hz) in SHR (n=56) than in WKY (n=38). Superfusion with angiotensin II (6 micromol/L) significantly depolarized the RVLM bulbospinal neurons in SHR (5.4+/-1.1 mV, n=15) but not in WKY. In contrast, candesartan (0.12 micromol/L) induced a significant membrane hyperpolarization (-3.7+/-0.4 mV; n=14) and a decrease in the firing rate in RVLM bulbospinal neurons of SHR but not of WKY. These results suggest that endogenously generated angiotensin II binds to type 1 receptors on RVLM bulbospinal neurons, thus tonically contributing to a higher membrane potential and a faster firing rate in SHR. The electrophysiological properties of RVLM neurons and their responses to angiotensin II and candesartan differ between neonatal WKY and SHR. These differences in RVLM neurons suggest a mechanism that possibly leads to elevation in blood pressure.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Oct
pubmed:issn
1524-4563
pubmed:author
pubmed:issnType
Electronic
pubmed:volume
40
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
560-5
pubmed:dateRevised
2010-11-18
pubmed:meshHeading
pubmed-meshheading:12364363-Action Potentials, pubmed-meshheading:12364363-Angiotensin II, pubmed-meshheading:12364363-Angiotensin Receptor Antagonists, pubmed-meshheading:12364363-Animals, pubmed-meshheading:12364363-Animals, Newborn, pubmed-meshheading:12364363-Benzimidazoles, pubmed-meshheading:12364363-Brain Stem, pubmed-meshheading:12364363-Cells, Cultured, pubmed-meshheading:12364363-Hypertension, pubmed-meshheading:12364363-Kinetics, pubmed-meshheading:12364363-Membrane Potentials, pubmed-meshheading:12364363-Neurons, pubmed-meshheading:12364363-Patch-Clamp Techniques, pubmed-meshheading:12364363-Rats, pubmed-meshheading:12364363-Rats, Inbred SHR, pubmed-meshheading:12364363-Rats, Inbred WKY, pubmed-meshheading:12364363-Receptor, Angiotensin, Type 1, pubmed-meshheading:12364363-Spinal Cord, pubmed-meshheading:12364363-Tetrazoles
pubmed:year
2002
pubmed:articleTitle
Rostral ventrolateral medulla neurons of neonatal Wistar-Kyoto and spontaneously hypertensive rats.
pubmed:affiliation
Department of Internal Medicine, Keio University School of Medicine, Shinjuku-ku, Tokyo, Japan.
pubmed:publicationType
Journal Article, Comparative Study