title: Effects of Amoxicillin and Clavulanic Acid on the Spontaneous Mechanical Activity of Juvenile Rat Duodenum.
abstract: OBJECTIVE
  There are a limited number of medications for the treatment of foregut dysmotility. Enteral amoxicillin/clavulanic acid induces phase III duodenal contractions in a fasting pediatric patient. The mechanism by which this occurs is unknown. We examined the individual contributions of amoxicillin and clavulanic acid on the spontaneous mechanical activity of juvenile rat duodenum to better understand this phenomenon.
  
  
  METHODS
  Duodenal segments from juvenile rats were longitudinally attached to force transducers in organ baths. Samples were cumulatively exposed to amoxicillin or clavulanic acid. Separate samples were exposed to carbachol alone to assess response in both the presence and absence of amoxicillin or clavulanic acid. Basal tone, frequency, and amplitude of contractions were digitized and recorded.
  
  
  RESULTS
  The amplitude of the spontaneous contractions increased with amoxicillin. Inhibition of neuronal activity prevented this effect. Clavulanic acid did not affect the spontaneous contractions. Basal tone and the rate of contractions did not differ with either drug. Stimulation with carbachol in the presence of amoxicillin caused a statistically significant increase in the contractility compared with carbachol alone.
  
  
  CONCLUSIONS
  Amoxicillin alters the spontaneous longitudinal mechanical activity of juvenile rat duodenum. Our results suggest that amoxicillin modulates the spontaneous pattern of cyclic mechanical activity of duodenal smooth muscle through noncholinergic, neurally mediated mechanisms. Our work provides an initial physiologic basis for the therapeutic use of amoxicillin in patients with gastrointestinal dysmotility.
authors.affiliation: Division of Pediatric Gastroenterology, Nationwide Children's Hospital, Columbus, Ohio.
authors.forename: Steven L
authors.initials: SL
authors.lastname: Ciciora
authors.forename: Kent C
authors.initials: KC
authors.lastname: Williams
authors.forename: Cheryl E
authors.initials: CE
authors.lastname: Gariepy
mesh_terms: D000658:Amoxicillin / Q000494:pharmacology*; D000818:Animals; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D002217:Carbachol / Q000378:metabolism; D019818:Clavulanic Acid / Q000494:pharmacology*; D004386:Duodenum / Q000187:drug effects* / Q000502:physiology; D005769:Gastrointestinal Motility / Q000187:drug effects*; D009119:Muscle Contraction / Q000187:drug effects; D009130:Muscle, Smooth / Q000187:drug effects; D051381:Rats; D011921:Rats, Inbred WKY; D065093:beta-Lactamase Inhibitors / Q000494:pharmacology*
chemical_list: D000900:Anti-Bacterial Agents; D065093:beta-Lactamase Inhibitors; D019818:Clavulanic Acid; D000658:Amoxicillin; D002217:Carbachol