The thromboxane receptors of rat and guinea-pig lung.
The thromboxane (TXA2) receptors on rat and guinea-pig lung strips were compared using TXA2 agonists and TXA2 receptor antagonists. On rat lung strip several TXA2 mimetics were full agonists whilst the primary prostanoids lacked agonist activity. On guinea-pig lung strip the same agonists displayed markedly different efficacies. Both preparations contained homogeneous populations of TXA2 receptors as evidenced by BAY u3405 giving comparable pA2 values against four TXA2 mimetics. However, the observed pA2's of nine different TXA2 receptor antagonists, determined against U46619, did not correlate between the two preparations. These results point to the existence of TXA2 receptor subtypes.
Norman
P
P
Research Department, Bayer plc, Stoke Poges, Slough, UK.
Cuthbert
N J
NJ
McKenniff
M G
MG
Gardiner
P J
PJ
D019796:15-Hydroxy-11 alpha,9 alpha-(epoxymethano)prosta-5,13-dienoic Acid; D000818:Animals; D001643:Bridged Bicyclo Compounds / Q000378:metabolism / Q000494:pharmacology; D019086:Bridged Bicyclo Compounds, Heterocyclic; D002227:Carbazoles / Q000378:metabolism / Q000494:pharmacology; D004305:Dose-Response Relationship, Drug; D005231:Fatty Acids, Unsaturated / Q000378:metabolism / Q000494:pharmacology; D006168:Guinea Pigs; D066298:In Vitro Techniques; D008168:Lung / Q000737:chemistry* / Q000187:drug effects / Q000502:physiology; D008297:Male; D009119:Muscle Contraction / Q000187:drug effects; D009130:Muscle, Smooth / Q000737:chemistry / Q000187:drug effects / Q000502:physiology; D011450:Prostaglandin Endoperoxides, Synthetic / Q000378:metabolism / Q000494:pharmacology; D051381:Rats; D017207:Rats, Sprague-Dawley; D017482:Receptors, Thromboxane / Q000037:antagonists & inhibitors / Q000187:drug effects / Q000378:metabolism*; D013449:Sulfonamides / Q000378:metabolism / Q000494:pharmacology; D013931:Thromboxanes / Q000037:antagonists & inhibitors
D001643:Bridged Bicyclo Compounds; D019086:Bridged Bicyclo Compounds, Heterocyclic; D002227:Carbazoles; D005231:Fatty Acids, Unsaturated; D011450:Prostaglandin Endoperoxides, Synthetic; D017482:Receptors, Thromboxane; D013449:Sulfonamides; D013931:Thromboxanes; C061750:7-(3-(3-hydroxy-4-(4'-iodophenoxy)-1-butenyl)-7-oxabicyclo(2.2.1)heptan-2-yl)-5-heptenoic acid; D019796:15-Hydroxy-11 alpha,9 alpha-(epoxymethano)prosta-5,13-dienoic Acid; C063119:ramatroban