title: Plasma concentrations of endothelin-like immunoreactivity in healthy horses and horses with naturally acquired gastrointestinal tract disorders.
abstract: OBJECTIVE
  To compare plasma endothelin (ET)- like immunoreactivity between healthy horses and those with naturally acquired gastrointestinal tract disorders.
  
  
  METHODS
  29 healthy horses and 142 horses with gastrointestinal tract disorders.
  
  
  METHODS
  Blood samples were collected from healthy horses and from horses with gastrointestinal tract disorders prior to treatment. Magnitude and duration of abnormal clinical signs were recorded, and clinical variables were assessed via thorough physical examinations. Plasma concentrations of ET-like immunoreactivity were measured by use of a radioimmunoassay for human endothelin-1, and CBC and plasma biochemical analyses were performed.
  
  
  RESULTS
  Plasma ET-like immunoreactivity concentration was significantly increased in horses with gastrointestinal tract disorders, compared with healthy horses. Median plasma concentration of ET-like immunoreactivity was 1.80 pg/ml (range, 1.09 to 3.2 pg/ml) in healthy horses. Plasma ET-like immunoreactivity was greatest in horses with strangulating large-intestinal obstruction (median, 10.02 pg/ml; range, 3.8 to 22.62 pg/ml), peritonitis (9.19 pg/ml; 789 to 25.83 pg/ml), and enterocolitis (8.89 pg/mI; 6.30 to 18.36 pg/ml). Concentration of ET-like immunoreactivity was significantly associated with survival, PCV, and duration of signs of pain. However, correlations for associations with PCV and duration of pain were low.
  
  
  CONCLUSIONS
  Horses with gastrointestinal tract disorders have increased plasma concentrations of ET-like immunoreactivity, compared with healthy horses. The greatest values were detected in horses with large-intestinal strangulating obstructions, peritonitis, and enterocolitis. This suggests a potential involvement of ET in the pathogenesis of certain gastrointestinal tract disorders in horses.
authors.affiliation: Department of Comparative Biomedical Sciences, School of Veterinary Medicine, Louisiana State University, Baton Rouge 70803-8410, USA.
authors.forename: Chidambaram M
authors.initials: CM
authors.lastname: Ramaswamy
authors.forename: Susan C
authors.initials: SC
authors.lastname: Eades
authors.forename: Changaram S
authors.initials: CS
authors.lastname: Venugopal
authors.forename: Giselle L
authors.initials: GL
authors.lastname: Hosgood
authors.forename: Frank
authors.initials: F
authors.lastname: Garza
authors.forename: Steven A
authors.initials: SA
authors.lastname: Barker
authors.forename: Rustin M
authors.initials: RM
authors.lastname: Moore
mesh_terms: D000818:Animals; D019332:Endothelin-1 / Q000096:biosynthesis / Q000097:blood*; D005767:Gastrointestinal Diseases / Q000097:blood / Q000662:veterinary*; D006400:Hematocrit / Q000662:veterinary; D006734:Horse Diseases / Q000097:blood*; D006736:Horses / Q000097:blood*; D016015:Logistic Models; D010146:Pain / Q000662:veterinary; D011863:Radioimmunoassay / Q000662:veterinary; D016019:Survival Analysis
chemical_list: D019332:Endothelin-1