title: Effect of sildenafil on gastric emptying and postprandial frequency of antral contractions in healthy humans.
abstract: BACKGROUND
  Sildenafil is known to block phosphodiesterase type 5, which degrades nitric oxide-stimulated cyclic guanosine monophosphate, thereby relaxing smooth muscle cells in various organs. The effect of sildenafil on gastric motor function after a meal was investigated in healthy humans.
  
  
  METHODS
  Ten healthy male volunteers (21-28 years) participated in a placebo-controlled, double-blind, cross-over study. In random order and on two separate days each volunteer ingested either 50 mg sildenafil (Viagra, Pfizer, New York, N.Y., USA) or placebo. A gamma camera technique was used to measure gastric emptying and postprandial frequency of antral contractions.
  
  
  RESULTS
  The area under the curve of gastric retention versus time of liquid or solid radiolabelled marker was not changed by sildenafil intake, nor was the postprandial frequency of antral contractions affected by sildenafil.
  
  
  CONCLUSIONS
  A single dose of 50 mg sildenafil does not change gastric emptying or postprandial frequency of antral contractions in healthy volunteers.
authors.affiliation: Dept. of Clinical Physiology and Nuclear Medicine, Hvidovre Hospital, University Hospital of Copenhagen, Copenhagen, Denmark.
authors.forename: J L
authors.initials: JL
authors.lastname: Madsen
authors.forename: S B
authors.initials: SB
authors.lastname: Søndergaard
authors.forename: S
authors.initials: S
authors.lastname: Fuglsang
authors.forename: J J
authors.initials: JJ
authors.lastname: Rumessen
authors.forename: J
authors.initials: J
authors.lastname: Graff
mesh_terms: D000328:Adult; D018592:Cross-Over Studies; D004311:Double-Blind Method; D005746:Gastric Emptying / Q000187:drug effects*; D006801:Humans; D008297:Male; D009119:Muscle Contraction / Q000187:drug effects*; D016065:Myoelectric Complex, Migrating / Q000187:drug effects; D010726:Phosphodiesterase Inhibitors / Q000494:pharmacology*; D010879:Piperazines / Q000494:pharmacology*; D019518:Postprandial Period / Q000187:drug effects*; D011687:Purines; D011706:Pyloric Antrum / Q000187:drug effects*; D012016:Reference Values; D000068677:Sildenafil Citrate; D013450:Sulfones; D013997:Time Factors
chemical_list: D010726:Phosphodiesterase Inhibitors; D010879:Piperazines; D011687:Purines; D013450:Sulfones; D000068677:Sildenafil Citrate