Catalogo Articoli (Spogli Riviste)

OPAC HELP

Titolo:
PHARMACOLOGICAL CHARACTERIZATION OF ENDOTHELIN RECEPTORS IN THE RABBIT IRIS SPHINCTER MUSCLE - SUGGESTION FOR THE PRESENCE OF ATYPICAL RECEPTORS
Autore:
ISHIKAWA H; HARUNO I; HARADA Y; YOSHITOMI T; ISHIKAWA S; KATORI M;
Indirizzi:
KITASATO UNIV,SCH MED,DEPT PHARMACOL,1-15-1 KITASATO SAGAMIHARA KANAGAWA 228 JAPAN KITASATO UNIV,SCH MED,DEPT PHARMACOL SAGAMIHARA KANAGAWA 228 JAPAN KITASATO UNIV,SCH MED,DEPT OPHTHALMOL SAGAMIHARA KANAGAWA 228 JAPAN
Titolo Testata:
Current eye research
fascicolo: 1, volume: 15, anno: 1996,
pagine: 73 - 78
SICI:
0271-3683(1996)15:1<73:PCOERI>2.0.ZU;2-1
Fonte:
ISI
Lingua:
ENG
Soggetto:
CELLULAR MECHANISM; ETA RECEPTOR; POTENT; CONTRACTION; SUBTYPES; CLONING; AGONIST; RELEASE; FAMILY; BQ-123;
Keywords:
BQ-123; ENDOTHELIN RECEPTOR; IRL 1620; RABBIT IRIS SPHINCTER; SARAFOTOXINS;
Tipo documento:
Article
Natura:
Periodico
Settore Disciplinare:
Science Citation Index Expanded
Citazioni:
35
Recensione:
Indirizzi per estratti:
Citazione:
H. Ishikawa et al., "PHARMACOLOGICAL CHARACTERIZATION OF ENDOTHELIN RECEPTORS IN THE RABBIT IRIS SPHINCTER MUSCLE - SUGGESTION FOR THE PRESENCE OF ATYPICAL RECEPTORS", Current eye research, 15(1), 1996, pp. 73-78

Abstract

Pharmacological profiles of endothelin (ET) receptors in the isolatedrabbit iris sphincter were characterized. ET isopeptides caused dose-dependent contraction of the preparation. The respective EC(50) valuesfor ET-1, ET-2 and ET-3 were 39.4, 58.0 and 84.3 nM, so that ET-1 wastwice as potent as ET-3. Sarafotoxin (SRTX) -b, an ET(A)/ET(B) non-selective agonist, caused very potent contraction with an EC(50) of 1.13nM. However, selective ET(B) receptor agonists SRTX-c and IRL 1620 showed no contractile activity up to 1 mu M. BQ-123, a selective ET(A) receptor antagonist, shifted the dose response curves of ET isopeptidesto the right. The pA(2) value for ET-1 was 5.52 with a slope of 1.06,which is not different from unity, and the pK(B) value for ET-2 was 5.06. Interestingly, very low doses of BQ-123 antagonized responses to ET-3 and SRTX-b, with a Schild plot slope of approximately 0.7 which is significantly different from unity, suggesting receptor heterogeneity. The abscissal intercepts of the Schild plots were -9.29 for ET-3 and -8.53 for SRTX-b. FR 139317, another ET(A) receptor antagonist, alsopreferentially antagonized responses to ET-3. RES-701-1, a selective ET(B) receptor antagonist, did not shift dose-response curves for ET-1and ET-3. These results suggest that ET receptors in the rabbit iris sphincter muscle cannot be classified into the ET(A), ET(B) or ET(C) receptor subtypes, so far established. When compared to the establishedreceptor subtypes, ET receptors in this preparation were quite different from the ET(B) receptor, but apparently showed a pharmacological profile most similar to the ET(A) receptor, suggesting the presence of heterogeneous and atypical ET(A) receptors.

ASDD Area Sistemi Dipartimentali e Documentali, Università di Bologna, Catalogo delle riviste ed altri periodici
Documento generato il 11/07/20 alle ore 21:13:22