Linked Life Data

1973609

Source:http://linkedlifedata.com/resource/pubmed/id/1973609

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:dateCreated
1990-8-21
pubmed:abstractText
In the rat gastric fundus, vasoactive intestinal polypeptide (VIP) contributes to the nonadrenergic noncholinergic (NANC) inhibitory neurotransmission and coexists with its related peptide, peptide histidine isoleucine (PHI). As the two neuropeptides are co-released and have similar actions in different biological systems, the effect of PHI in the rat gastric fundus was studied in order to investigate whether it might be a co-transmitter of VIP in the inhibitory NANC neurotransmission in this tissue. Auxotonic responses were measured in longitudinal muscle strips from the gastric fundus of reserpinized rats (5 mg/kg i.p., 24 hr before sacrifice), suspended between parallel platinum electrodes in Krebs solution containing atropine (1 microM) and 5-hydroxytryptamine (3 microM). PHI induced concentration-dependent relaxations (10 nM-1 microM), qualitatively similar to those induced by electrical field stimulation (1 msec, supramaximal voltage, 0.25-16 Hz) and by VIP (0.3-100 nM), although PHI was about 30 times less potent than VIP. The submaximal relaxation induced by PHI (100 nM) was not influenced by tetrodotoxin (1 microM), hexamethonium (500 microM) and propranolol (10 microM) plus phentolamine (3 microM). Incubation during 60 min with a specific PHI-antiserum completely prevented the relaxation induced by PHI (100 nM) and reduced by 26% that induced by electrical field stimulation at 1 Hz; the procedure had no influence on the relaxation induced by VIP (3 nM) or isopropylnoradrenaline (10 nM). Incubation during 60 min with a specific VIP-antiserum completely prevented the relaxation induced by VIP (3 nM) and halved the relaxatory response to electrical field stimulation at 1 Hz, while it had no influence on the relaxation induced by PHI (100 nM) or isopropylnoradrenaline (10 nM). Control serum had no influence on any of the relaxant stimuli. In conclusion, PHI mimics the electrically induced NANC relaxation in the rat gastric fundus; its action is located at muscle level and does not involve alpha-, beta- or nicotinic receptors. The results obtained in the presence of the antisera provide further confirmation that VIP contributes to the NANC inhibitory neurotransmission of the rat gastric fundus and leave open the possibility that PHI is involved as co-transmitter.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:issn
0301-4533
pubmed:author
pubmed:issnType
Print
pubmed:volume
303
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
216-31
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:articleTitle
Is peptide histidine isoleucine an inhibitory nonadrenergic noncholinergic neurotransmitter in the rat gastric fundus?
pubmed:affiliation
Institute of Pharmacology, Catholic University School of Medicine, Rome, Italy.
pubmed:publicationType
Journal Article, In Vitro, Research Support, Non-U.S. Gov't