Inhibition of the pulmonary inactivation of prostaglandins in vivo by di-4-phloretin phosphate.
1 Inactivation of prostaglandin E2 in the pulmonary circulation of rabbits in vivo was measured by comparing the hypotensive effects of doses given intravenously and intra-arterially. 2 Di-4-phloretin phosphate (DPP) 25-100 mug kg-1 min-1 inhibited the inactivation of prostaglandin E2 in the pulmonary circulation. 3 These doses of DPP caused a marked shift to the left of the dose-response curve to prostaglandin E2 given intravenously but did not affect the dose-response curve to prostaglandin E2 given intra-arterially. 4 Inhibition of pulmonary inactivation of prostaglandins E2 and F2alpha caused marked potentiation of their gastrointestinal effects. 5 At these doses antagonism of the hypotensive action of prostaglandin E2 by DPP was seldom seen but the gastrointestinal effect of prostaglandin F2alpha was sometimes antagonized. 6 After treatment with DPP 100 mug kg-1 min-1, high doses of prostaglandin were sometimes lethal.
D000818:Animals; D001794:Blood Pressure / Q000187:drug effects; D003864:Depression, Chemical; D005769:Gastrointestinal Motility / Q000187:drug effects; D066298:In Vitro Techniques; D008168:Lung / Q000378:metabolism*; D008297:Male; D010693:Phloretin / Q000031:analogs & derivatives*; D011121:Polyphloretin Phosphate / Q000494:pharmacology*; D011453:Prostaglandins / Q000378:metabolism*; D011458:Prostaglandins E / Q000378:metabolism / Q000494:pharmacology; D011460:Prostaglandins F / Q000494:pharmacology; D011817:Rabbits; D013268:Stimulation, Chemical
D011453:Prostaglandins; D011458:Prostaglandins E; D011460:Prostaglandins F; D011121:Polyphloretin Phosphate; D010693:Phloretin