title: Sildenafil improves clinical signs and radiographic features in dogs with congenital idiopathic megaoesophagus: a randomised controlled trial.
abstract: We evaluated the efficacy of oral sildenafil citrate in dogs with congenital idiopathic megaoesophagus (CIM). Twenty-one puppies were randomly assigned to two groups (treatment and control). The dogs were given sildenafil oral suspension 1 mg/kg every 12 hours for 14 days or placebo in a masked fashion. Clinical signs (frequency of regurgitation and weight gain) and oesophagrams (relative oesophageal diameter, ROD) were evaluated in order to assess the efficacy of drug treatment, by examiners who were unaware of the study protocol. In addition, a set of in vitro experiments on isolated samples of canine lower oesophageal sphincter (LOS) was performed, and the effects of increasing concentrations of sildenafil on basal tone and electrically-stimulated motility were assessed. Sildenafil administration significantly reduced the number of regurgitation episodes (0.88±1.40 v 2.65±1.56, P<0.0001) and significantly increased weight gain in the treated dogs compared to controls (79.76±28.30 per cent v 53.40±19.30 per cent, P=0.034). ROD values, at the end of the treatment period, were significantly decreased in the sildenafil group, compared to pre-treatment values (0.97±0.19 v 0.24±0.14, P<0.0001), in contrast to control subjects (0.98±0.17 v 1.10±0.25, P=0.480). In accordance with the in vivo findings, sildenafil dose-dependently reduced basal tone and increased electrically-induced relaxation of dog LOS samples. These results suggest that sildenafil citrate helps ameliorate clinical and radiographic signs in dogs with CIM by reducing LOS tone, and could represent a novel therapeutic tool for the treatment of this disease.
authors.affiliation: Department of Veterinary Science, University of Parma, Parma, Italy.
authors.forename: F
authors.initials: F
authors.lastname: Quintavalla
authors.affiliation: Department of Veterinary Science, University of Parma, Parma, Italy.
authors.forename: A
authors.initials: A
authors.lastname: Menozzi
authors.affiliation: Department of Neuroscience, University of Parma, Parma, Italy.
authors.forename: C
authors.identifier: http://orcid.org/0000-0003-3898-6779
authors.initials: C
authors.lastname: Pozzoli
authors.affiliation: Department of Neuroscience, University of Parma, Parma, Italy.
authors.forename: E
authors.initials: E
authors.lastname: Poli
authors.affiliation: Cerro Maggiore, Milano, Italy.
authors.forename: P
authors.initials: P
authors.lastname: Donati
authors.affiliation: The Animal Medical Hospital and Whitestone Veterinary Care, New York, NY, USA.
authors.forename: D K
authors.initials: DK
authors.lastname: Wyler
authors.affiliation: Department of Veterinary Science, University of Parma, Parma, Italy.
authors.forename: P
authors.initials: P
authors.lastname: Serventi
authors.affiliation: Department of Veterinary Science, University of Parma, Parma, Italy.
authors.forename: S
authors.initials: S
authors.lastname: Bertini
mesh_terms: D000818:Animals; D004283:Dog Diseases / Q000151:congenital* / Q000000981:diagnostic imaging / Q000188:drug therapy*; D004285:Dogs; D004931:Esophageal Achalasia / Q000151:congenital / Q000000981:diagnostic imaging / Q000188:drug therapy / Q000662:veterinary*; D005260:Female; D008297:Male; D011859:Radiography / Q000662:veterinary; D000068677:Sildenafil Citrate / Q000627:therapeutic use*; D016896:Treatment Outcome
chemical_list: D000068677:Sildenafil Citrate
keywords: LOS; dog; megaoesophagus; sildenafil