title: The structural conformation of the polyphosphate chain of the ATP molecule is critical for its promotion of prostaglandin biosynthesis.
abstract: The adenine nucleotide ATP relaxed the tracheal strip of the guinea pig, while the methylene isosteres of ATP, alpha, beta-methylene ATP (APCPP) and beta, gamma-methylene ATP (APPCP) in concentrations up to 100 micrograms were either inactive or produced a small contraction. The relaxation of the tracheal strip elicited by ATP was completely abolished by treatment of the tissue with indomethacin, a prostaglandin synthesis inhibitor. The relaxations induced by ATP in the guinea-pig taenia coli were followed by a rebound contraction which could be blocked by indomethacin. The two methylene analogues of ATP, produced relaxations in the taenia coli which were not followed by a rebound contraction. It is concluded that in the guinea-pig tracheal chain and taenia coli preparations ATP stimulated prostaglandin synthesis while the analogues modified in the polyphosphate chain were unable to do so.
mesh_terms: D000255:Adenosine Triphosphate / Q000031:analogs & derivatives / Q000494:pharmacology*; D000818:Animals; D003106:Colon / Q000378:metabolism; D005260:Female; D006168:Guinea Pigs; D066298:In Vitro Techniques; D007213:Indomethacin / Q000494:pharmacology; D008297:Male; D008968:Molecular Conformation; D009130:Muscle, Smooth / Q000378:metabolism; D011453:Prostaglandins / Q000096:biosynthesis*; D013329:Structure-Activity Relationship; D014132:Trachea / Q000378:metabolism
chemical_list: D011453:Prostaglandins; D000255:Adenosine Triphosphate; D007213:Indomethacin