title: A dog model to study ovary, ovarian ligament and visceral pain.
abstract: OBJECTIVE
  A dog model was developed to study visceral pain by stimulating the ovarian ligament.
  
  
  METHODS
  Prospective experimental trial.
  
  
  METHODS
  Twelve 1-year old female hound dogs weighing 25.7 ± 3.6 kg.
  
  
  METHODS
  Dogs were anesthetized with sevoflurane. The right ovary was accessed via laparoscopy. A suture was placed around the ovarian ligament and exteriorized through the abdominal wall for stimulation. The noxious stimulus consisted of pulling the ovary and ovarian ligament with a force transducer. The response to noxious stimulation was determined using the anesthetic minimum alveolar concentration requirement (MAC) for sevoflurane. The ovarian MAC was compared to the standardized somatic noxious stimulation tail clamp MAC. The results are depicted as mean ± SD and corrected to sea-level.
  
  
  RESULTS
  The stimulus-response curve during ovarian stimulation in three dogs was hyperbolic and best represented by a three-parameter logistic growth curve model. The curve plateaued at 7.12 ± 4.19 N. From the stimulus-response curve, we chose 6.61 N to test the consistency and repeatability of the model in nine dogs. The ovarian stimulation MAC for sevoflurane in these dogs was 2.16 ± 0.46%. The ovarian stimulation confidence interval and limits are comparable to the results from tail stimulation MAC. The tail stimulation MACs before and after laparoscopy surgery were not different (1.86 ± 0.28% and 1.77 ± 0.38% respectively; p > 0.05) but lower when compared to the ovarian MAC (p < 0.01). The dogs recovered from anesthesia without complications.
  
  
  CONCLUSIONS
  The ovarian stimulation model is an adequate and repeatable means of producing visceral stimulation to determine MAC. The model may provide a humane mechanism to study the effectiveness of analgesics for acute ovarian pain.
authors.affiliation: Department of Clinical Sciences, Veterinary Teaching Hospital, Colorado State University, Fort Collins, CO 80523, USA. pboscan@colostate.edu
authors.forename: Pedro
authors.initials: P
authors.lastname: Boscan
authors.forename: Eric
authors.initials: E
authors.lastname: Monnet
authors.forename: Khursheed
authors.initials: K
authors.lastname: Mama
authors.forename: David C
authors.initials: DC
authors.lastname: Twedt
authors.forename: Jonathan
authors.initials: J
authors.lastname: Congdon
authors.forename: Jens C
authors.initials: JC
authors.lastname: Eickhoff
authors.forename: Eugene P
authors.initials: EP
authors.lastname: Steffey
mesh_terms: D000769:Anesthesia, Inhalation / Q000662:veterinary*; D018685:Anesthetics, Inhalation / Q000493:pharmacokinetics; D000818:Animals; D004195:Disease Models, Animal; D004285:Dogs; D005260:Female; D010535:Laparoscopy / Q000662:veterinary; D008022:Ligaments / Q000503:physiopathology*; D008738:Methyl Ethers / Q000493:pharmacokinetics; D010053:Ovary / Q000503:physiopathology*; D017699:Pelvic Pain; D011446:Prospective Studies; D011650:Pulmonary Alveoli / Q000378:metabolism*; D015203:Reproducibility of Results; D000077149:Sevoflurane
chemical_list: D018685:Anesthetics, Inhalation; D008738:Methyl Ethers; D000077149:Sevoflurane