Linked Life Data

2426443

Source:http://linkedlifedata.com/resource/pubmed/id/2426443

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2
pubmed:dateCreated
1986-9-17
pubmed:abstractText
Transmural nerve stimulation (TNS) of the right atria in vitro produced positive and negative chronotropic responses in rats and guinea pigs. The negative component appeared only temporarily soon after the cessation of TNS and was usually masked by the positive component. The positive and negative chronotropic responses were accompanied by an increase and decrease in contractile force, respectively. Atenolol (3 X 10(-6) M) decreased and atropine (10(-6) M) potentiated the TNS-induced positive chronotropic response. In the presence of both atenolol and atropine, TNS accelerated the heart rate markedly in the right atria of guinea pigs and slightly in those of rats. TNS-induced acceleration of the heart rate was also observed in surgically sympathectomized or reserpine-pretreated (5 mg/kg/48 hr and 2.5 mg/kg/24 hr i.p.) right atrium, in which tyramine (up to 10(-4) M) exerted no appreciable effect. Inasmuch as tetrodotoxin (10(-6) M) almost abolished the TNS-induced chronotropic response, this atenolol- and atropine-resistant response is likely mediated by nonadrenergic noncholinergic (NANC) nerve(s). The NANC nerve-mediated positive chronotropic response was not affected by diphenhydramine (10(-6) M), cimetidine (10(-6) M), methysergide (10(-6) M) and hexamethonium (3 X 10(-6) M). The NANC nerve-mediated response was relatively slow at the onset yet long-lasting compared with adrenergic and cholinergic responses, suggesting that the neurotransmitter of the NANC nerve is a certain substance which may be inactivated more slowly than biogenic amines. Histochemical studies demonstrated the presence of vasoactive intestinal polypeptide-like and substance P-like immunoreactive nerves in the right atrium, as well as catecholamine-fluorescence and acetylcholinesterase-positive nerves.(ABSTRACT TRUNCATED AT 250 WORDS)
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Aug
pubmed:issn
0022-3565
pubmed:author
pubmed:issnType
Print
pubmed:volume
238
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
713-9
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1986
pubmed:articleTitle
Pharmacological analysis of autonomic innervation of the right atria of rats and guinea pigs: demonstration of nonadrenergic noncholinergic nerves.
pubmed:publicationType
Journal Article, In Vitro, Research Support, Non-U.S. Gov't