New agonist and antagonist analogues of bradykinin

1984 ◽  
Vol 62 (6) ◽  
pp. 627-629 ◽  
Author(s):  
J. Barabé ◽  
S. Caranikas ◽  
P. D'Orléans-Juste ◽  
D. Regoli
Keyword(s):  
Guinea Pig ◽  
Jugular Vein ◽  
Rabbit Aorta ◽  
Guinea Pig Ileum ◽  
Receptor System ◽  
Relative Affinity ◽  
Agonist And Antagonist

Three new analogues of bradykinin (BK) have been tested for their agonistic and antagonistic actions on the rabbit jugular vein and the guinea pig ileum (B2 receptors), and six were studied on rabbit aorta strips (B1 receptors). Substitution of Gly4, Phe5, and Phe8 in BK with D-Trp gives analogues with a relative affinity lower than 1.0% as compared with BK. These analogues have no antagonistic properties on the rabbit jugular vein and on guinea pig ileum (B2 receptors). Substitution of Pro7 in des-Arg9-BK by Gly and by D-Ala give compounds that antagonise the effects of kinins on the rabbit aorta strips (B1-receptor system). These new antagonists are fairly potent with a pA2 value of 6.03 to 7.29 and seem competitive because the pA2 – pA10 values approximate 0.95. These results suggest that the orientation of Phe8 is critical for the activation of B1 receptors by kinins.

Characterization of bradykinin receptors in peripheral organs

1991 ◽  
Vol 69 (7) ◽  
pp. 938-943 ◽  
Author(s):  
Nour-Eddine Rhaleb ◽  
Noureddine Rouissi ◽  
Guy Drapeau ◽  
Daniela Jukic ◽  
Domenico Regoli
Keyword(s):  
Urinary Bladder ◽  
Guinea Pig ◽  
Jugular Vein ◽  
Smooth Muscles ◽  
Rabbit Aorta ◽  
Arachidonic Acid Cascade ◽  
Receptor System ◽  
Kinin Receptors ◽  
Concentration Levels

Bradykinin (BK) and related kinins are potent stimulants of the rabbit jugular vein, the hamster urinary bladder, and the guinea pig trachea. The characterization of kinin receptors in these tissues was made with agonists and antagonists. Results obtained with agonists indicate that bradykinin and kallidin are much more active than des-Arg9-BK and suggest the presence of B2 receptors in the three organs. Some new agonists were also tested and the BK analogue, [Hyp3,Tyr(Me)8]BK, was found to be a potent and selective stimulant of the three preparations, with pD2 values of 8.56, 8.00, and 8.39, respectively, but inactive on the rabbit aorta (a B1-receptor system). Contractile effects of kinins in the rabbit jugular vein and hamster urinary bladder were reduced or eliminated by B2-receptor antagonists but at different concentration levels; e.g., acetyl-D-Arg[Hyp3,D-Phe7]BK showed pA2 values of 7.78 on the rabbit jugular vein but only 5.72 on hamster urinary bladder. This compound contracted the guinea-pig trachea and was found to be inactive as an antagonist on this preparation. Contractions of the hamster urinary bladder and the guinea-pig trachea in response to bradykinin were markedly reduced or eliminated by indomethacin and by BW 755C, while those of the rabbit jugular vein were not modified. The present findings indicate that the myotropic effect of kinins on the rabbit jugular vein depends on the activation of B2 receptors and suggest that B2 receptors are largely responsible also for the response of the hamster urinary bladder. B2 receptors and (or) a nonreceptor mechanism appear to be involved in the stimulant effects of the kinin agonists and some antagonists in the guinea-pig trachea.Key words: bradykinin, B2 receptors, agonists, antagonists, smooth muscles, arachidonic acid cascade, indomethacin, BW 755C.

The effect of several α-adrenoceptor antagonists on the response to histamine in various tissues

1980 ◽  
Vol 58 (1) ◽  
pp. 40-44 ◽  
Author(s):  
K. M. MacLeod ◽  
C. A. Krueger ◽  
D. Smith ◽  
D. M. Iwanow ◽  
D. A. Cook
Keyword(s):  
Guinea Pig ◽  
Portal Vein ◽  
Right Ventricle ◽  
Induced Response ◽  
Guinea Pig Ileum ◽  
Receptor System ◽  
Guinea Pig Heart ◽  
Rabbit Portal Vein ◽  
Histamine Response ◽  
Antagonist Effect

The effect of various α-receptor antagonists on the histamine-induced response of guinea pig ileum, guinea pig heart, and rabbit portal vein have been studied. In guinea pig ileum, an H1 receptor system, phenoxybenzamine and dibozane are effective antagonists, phentolamine is a weak antagonist, azapetine is without antagonist effect, and tolazoline is a weak agonist. In the H2 system of guinea pig right ventricle, phentolamine and azapetine are antagonists, phenoxybenzamine and dibozane are inactive, and tolazoline is an agonist. All antagonists except tolazoline block the histamine response in portal vein which is believed to be mediated by a receptor of low selectivity. Tolazoline is an agonist in portal vein.

Anti-inflammatory effect of Mitragyna speciosa crude methanol extract on the guinea pig ileum

Planta Medica ◽  
2009 ◽  
Vol 75 (09) ◽  
Author(s):  
WM Shaik Mossadeq ◽  
K Syamimi ◽  
MP Azyyati ◽  
ZA Zakaria ◽  
AK Arifah ◽  
...  
Keyword(s):  
Guinea Pig ◽  
Methanol Extract ◽  
Guinea Pig Ileum ◽  
Mitragyna Speciosa ◽  
Anti Inflammatory ◽  
Crude Methanol Extract ◽  
Inflammatory Effect

Preparation and properties of three analogues of [5-leucine]enkephalin, substrates for enzyme conversion studies

1985 ◽  
Vol 50 (6) ◽  
pp. 1329-1334
Author(s):  
Jaroslav Vičar ◽  
Linda Servítová ◽  
Martin Flegel ◽  
Karel Hauzer ◽  
Tomislav Barth
Keyword(s):  
High Pressure ◽  
Liquid Chromatography ◽  
Guinea Pig ◽  
Ion Exchange Chromatography ◽  
Exchange Chromatography ◽  
Guinea Pig Ileum ◽  
Opioid Activity ◽  
C Terminus ◽  
N Terminus ◽  
Fragment Condensation

Analogues of [5-Leu]enkephalin, prolonged by methionine on the N-terminus or, by lysine or methionine on the C-terminus were prepared by fragment condensation, purified by ion exchange chromatography or high-pressure liquid chromatography. The substances were characterised by their opioid activity in a test on guinea-pig ileum in comparison with the activity of [5-Leu]enkephalin.

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