title: Proton pump inhibitors omeprazole, lansoprazole and pantoprazole induce relaxation in the rat lower oesophageal sphincter.
abstract: OBJECTIVE
  We aimed to investigate effects of the proton pump inhibitors (PPIs) omeprazole, lansoprazole and pantoprazole, which are currently used for the treatment of hyperacidity and gastro-oesophageal reflux, on the reactivity of the isolated rat lower oesophageal sphincter.
  
  
  METHODS
  Omeprazole, lansoprazole and pantoprazole (all 10(-9) -10(-3) m, cumulatively) were tested on carbachol-induced (10(-6) m) contraction. In addition, the effects of PPI preincubation (all 10(-3) m) on the contractions induced by cumulative carbachol (10(-9) -10(-5) m), angiotensin-2 (10(-9) -10(-5) m) or electrical field stimulation (EFS; 40 V, 32 Hz, 1 ms, 10 s) were assessed. Finally, the effects of PPI on the spontaneous contractile activity of the tissue were also evaluated.
  
  
  RESULTS
  PPI relaxed precontracted lower oesophageal sphincter in a concentration-dependent manner and suppressed carbachol-, angiotensin- and EFS-induced contractions. Furthermore, PPI attenuated spontaneous contractile activity of the tissue.
  
  
  CONCLUSIONS
  Omeprazole, lansoprazole and pantoprazole had a suppressor effect on lower oesophageal sphincter contractions.
authors: Department of Pharmacology, Medical Faculty, Mersin University Campus Yenişehir, Mersin, Turkey.
authors: A Sencer
authors: AS
authors: Yurtsever
authors: Mehtap
authors: M
authors: Pektas
authors: Mehtap
authors: M
authors: Ozkur
authors: Ismail
authors: I
authors: Un
authors: Aydin
authors: A
authors: Erenmemisoglu
authors: Kansu
authors: K
authors: Buyukafsar
mesh_terms: D053799:2-Pyridinylmethylsulfinylbenzimidazoles / Q000494:pharmacology*; D000809:Angiotensins; D000818:Animals; D002217:Carbachol / Q000494:pharmacology; D004558:Electric Stimulation; D049630:Esophageal Sphincter, Lower / Q000187:drug effects* / Q000502:physiology; D005764:Gastroesophageal Reflux; D064747:Lansoprazole; D009126:Muscle Relaxation / Q000187:drug effects*; D009130:Muscle, Smooth / Q000187:drug effects*; D009853:Omeprazole / Q000494:pharmacology*; D000077402:Pantoprazole; D054328:Proton Pump Inhibitors / Q000494:pharmacology*; D051381:Rats; D017208:Rats, Wistar
chemical_list: D053799:2-Pyridinylmethylsulfinylbenzimidazoles; D000809:Angiotensins; D054328:Proton Pump Inhibitors; D064747:Lansoprazole; D002217:Carbachol; D000077402:Pantoprazole; D009853:Omeprazole