title: In vitro effects of famotidine and ranitidine on lower esophageal sphincter tone in rats.
abstract: OBJECTIVE
  The aim of this study was to investigate the effects of the H2 receptor antagonists famotidine and ranitidine on lower esophageal sphincter pressure in the rat isolated lower esophageal sphincter preparation contracted with carbachol.
  
  
  METHODS
  Lower esophageal sphincter tissues of eight rats for each group were placed in a standard organ bath. After contraction with carbachol, freshly prepared famotidine and ranitidine were added directly to the tissue bath in cumulatively increasing concentrations. Activities were recorded on an online computer using the software BSL PRO v 3.7, which also analyzed the data.
  
  
  RESULTS
  Ranitidine caused a small statistically insignificant relaxation in the contracted lower esophageal sphincter at the two applied concentrations. Although 1.5 x 10⁻⁵ M famotidine did not cause a significant relaxation in lower esophageal sphincter tone, this value for 4.5 x 10⁻⁵ M famotidine was 9.33%, and the relaxation was significant when compared with controls (p<0.05).
  
  
  CONCLUSIONS
  Neither famotidine nor ranitidine caused any direct significant change in lower esophageal sphincter tone in the therapeutic dose range applied to the organ bath. However, the higher dose of famotidine caused a significant relaxation in the lower esophageal sphincter tone. Further in vivo human studies may affect the usage of these drugs during gastroesophageal reflux disease treatment.
authors.affiliation: Department of Pharmacology, Yeditepe University, School of Medicine, İstanbul, Turkey.
authors.forename: Mahmut
authors.initials: M
authors.lastname: Özer
authors.forename: Mustafa
authors.initials: M
authors.lastname: Duman
authors.forename: Şükrü
authors.initials: Ş
authors.lastname: Taş
authors.forename: Yeliz
authors.initials: Y
authors.lastname: Demırcı
authors.forename: Muhammet Fatih
authors.initials: MF
authors.lastname: Aydin
authors.forename: Enver
authors.initials: E
authors.lastname: Reyhan
authors.forename: Ali Emre
authors.initials: AE
authors.lastname: Atici
authors.forename: Erdal Birol
authors.initials: EB
authors.lastname: Bostanci
authors.forename: Musa
authors.initials: M
authors.lastname: Akoğlu
authors.forename: Ece
authors.initials: E
authors.lastname: Genç
mesh_terms: D000818:Animals; D004195:Disease Models, Animal; D049630:Esophageal Sphincter, Lower / Q000187:drug effects* / Q000503:physiopathology; D015738:Famotidine / Q000627:therapeutic use*; D005764:Gastroesophageal Reflux / Q000188:drug therapy* / Q000503:physiopathology; D006635:Histamine H2 Antagonists / Q000627:therapeutic use; D009129:Muscle Tonus / Q000187:drug effects*; D010528:Peristalsis / Q000187:drug effects*; D011899:Ranitidine / Q000627:therapeutic use*; D051381:Rats
chemical_list: D006635:Histamine H2 Antagonists; D015738:Famotidine; D011899:Ranitidine