Characterisation of the prostanoid receptors mediating contraction of guinea-pig isolated trachea.
The receptors mediating prostanoid-induced contraction of guinea-pig isolated trachea have been characterised in terms of a recently proposed general classification of prostanoid receptors. Results obtained on the trachea were compared with those obtained on guinea-pig fundus, which contains a sub-type of PGE2-sensitive (EP-) receptor termed the EP1-receptor, and guinea-pig lung strip, which contains a thromboxane-sensitive or TP-receptor. The following agonists were studied, PGE2, PGF2 alpha and the thromboxane-like agonists U-46619 and Wy17186. The antagonists studied were SC-19220 which selectively blocks EP1-receptors, and AH19437 which selectively blocks TP-receptors. On guinea-pig fundus the rank order of agonist potency was PGE2 greater than PGF2 alpha greater than Wy-17186 approximately equal to U-46619, and responses to all agonists were antagonised by SC-19220 but not by AH19437. On guinea-pig lung strip the rank order of potency was U-46619 greater than Wy17186 much greater than PGF2 alpha greater than PGE2 and responses to all agonists tested were blocked by AH19437 but not by SC-19220. On the trachea, the rank order was PGE2 = U-46619 greater than Wy17186 = PGF2 alpha. SC-19220 antagonised responses to PGE2 and PGF2 alpha, but not those to U-46619 or Wy17186. Conversely, AH19437 antagonised responses to U-46619 and Wy17186 but not those to PGE2 or PGF2 alpha. It is concluded that prostanoid-induced contractions of guinea-pig trachea can be mediated by both EP1- and TP-receptors.
Coleman
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Kennedy
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D019796:15-Hydroxy-11 alpha,9 alpha-(epoxymethano)prosta-5,13-dienoic Acid; D000818:Animals; D015237:Dinoprost; D015232:Dinoprostone; D005260:Female; D006168:Guinea Pigs; D008168:Lung / Q000187:drug effects; D008297:Male; D009119:Muscle Contraction / Q000187:drug effects*; D011450:Prostaglandin Endoperoxides, Synthetic / Q000494:pharmacology; D011458:Prostaglandins E / Q000494:pharmacology; D011459:Prostaglandins E, Synthetic / Q000494:pharmacology; D011460:Prostaglandins F / Q000494:pharmacology; D011956:Receptors, Cell Surface / Q000378:metabolism*; D011982:Receptors, Prostaglandin / Q000378:metabolism*; D013270:Stomach / Q000187:drug effects; D014132:Trachea / Q000187:drug effects*
D011450:Prostaglandin Endoperoxides, Synthetic; D011458:Prostaglandins E; D011459:Prostaglandins E, Synthetic; D011460:Prostaglandins F; D011956:Receptors, Cell Surface; D011982:Receptors, Prostaglandin; C045532:Wy 17186; D019796:15-Hydroxy-11 alpha,9 alpha-(epoxymethano)prosta-5,13-dienoic Acid; D015237:Dinoprost; D015232:Dinoprostone