title: Intramural Injection with Botulinum Toxin Type A in Piglet Esophagus. The Influencer on Maximum Load and Elongation: A Dose Response Study.
abstract: Introduction The treatment of esophageal atresia (OA) is challenging. The main goal is to achieve primary anastomosis. We have previously demonstrated in a pig model that intramural injection of botulinum toxin type A (BTX-A) resulted in significant elongation of the esophagus during tensioning until bursting point. The objectives of the present study were to investigate the influence of different amounts of intramural BTX-A on the stretch-tension characteristics and histological changes of the esophagus in piglets. Materials and Methods A total of 52 piglets were randomized to four groups receiving 2, 4, or 8 units/kg of BTX-A or isotonic saline (placebo). After a 1-hour of rest the esophagus was harvested and subjected to a stretch-tension test and histological examination to assess changes in the density of presynaptic vesicles in the nerve cells. Results Overall, 9 of the 52 animals were excluded from analysis due to problems with the stretch-tension test or death from anesthesia. The maximum loads were higher in the BTX-A groups (2 units/kg: +2.1 N; 4 units/kg: +1.3 N; 8 units/kg: +1.9 N) than the placebo (p = 0.046). There were no significant differences in percentage elongation, or histology. Conclusions This study demonstrated that injection of 2 units/kg BTX-A into a nonanastomosed esophageal wall resulted in a modest increase in the maximum load achieved before bursting; this may be due to the muscle-relaxant effect of BTX-A. BTX-A injection produced no significant effects on elongation or esophageal histology. The clinical usefulness of BTX-A in treatment of OA is still unclear.
authors.affiliation: Department of Surgery, Odense University Hospital, Odense, Denmark.
authors.forename: Mark Bremholm
authors.initials: MB
authors.lastname: Ellebæk
authors.affiliation: Department of Surgery, Odense University Hospital, Odense, Denmark.
authors.forename: Niels
authors.initials: N
authors.lastname: Qvist
authors.affiliation: Department of Clinical Pathology, Odense University Hospital, Odense, Denmark.
authors.forename: Henrik Daa
authors.initials: HD
authors.lastname: Schrøder
authors.affiliation: Department of Surgery, Odense University Hospital, Odense, Denmark.
authors.forename: Lars
authors.initials: L
authors.lastname: Rasmussen
mesh_terms: D000818:Animals; D019274:Botulinum Toxins, Type A / Q000008:administration & dosage*; D004305:Dose-Response Relationship, Drug; D004933:Esophageal Atresia / Q000188:drug therapy; D004947:Esophagus / Q000187:drug effects*; D007273:Injections, Intramuscular; D008297:Male; D009465:Neuromuscular Agents / Q000008:administration & dosage*; D011897:Random Allocation; D013552:Swine; D013718:Tensile Strength / Q000187:drug effects* / Q000502:physiology
chemical_list: D009465:Neuromuscular Agents; D019274:Botulinum Toxins, Type A