title: Development and validation of an assay for measurement of leptin in pig saliva.
abstract: BACKGROUND
  Leptin has been measured in human in saliva samples. However, the low leptin concentration found in this biological fluid makes necessary the use of high sensitive methods. To the authors' knowledge, leptin has not been measured in porcine saliva. This study aimed to develop and validate a time-resolved immunofluorometric assay (TR-IFMA) for salivary leptin measurements in pigs, using a species-specific antibody, and to evaluate how salivary leptin changes with body weight, food ingestion, and in experimental models of stress and inflammation. Polyclonal antibodies were produced in rabbits immunized with recombinant porcine leptin and used to develop a sandwich TR-IFMA.
  
  
  RESULTS
  The method had intra-assay and inter-assay coefficients of variation lower than 10 and 16 %, respectively. The assay was accurate and the low limit of detection allowed detection of leptin in all analyzed samples. Salivary leptin concentration was positively correlated to body weight (r = 0.58, P = 0.01) and increased after food ingestion (P < 0.001) and after 24 h of applying a model of experimental inflammation by turpentine injection (P < 0.05). However, it did not significantly change after a model of acute stress consisting of a nose snare restraining.
  
  
  CONCLUSIONS
  These results indicate that the developed assay can measure leptin in porcine saliva in a reliable way and that leptin in saliva is influenced by body weight, food ingestion and inflammation.
authors: Department of Veterinary Clinical Sciences, School of Veterinary Medicine and Animal Science, São Paulo State University (FMVZ - UNESP), campus of Botucatu. Rua Dr. Walter Maurício Correa, s/n, Botucatu, SP, 18618-681, Brazil.
authors: Elizabeth M S
authors: EM
authors: Schmidt
authors: Interdisciplinary Laboratory of Clinical Analysis (Interlab-UMU), Veterinary Clinical Hospital, Campus of Excellence Mare Nostrum, University of Murcia, Espinardo-Murcia, 30100, Spain.
authors: Damián
authors: D
authors: Escribano
authors: Interdisciplinary Laboratory of Clinical Analysis (Interlab-UMU), Veterinary Clinical Hospital, Campus of Excellence Mare Nostrum, University of Murcia, Espinardo-Murcia, 30100, Spain.
authors: Silvia
authors: S
authors: Martinez-Subiela
authors: Animal Production Department, Veterinary School, Campus of Excellence Mare Nostrum, University of Murcia, Espinardo-Murcia, 30100, Spain.
authors: Silvia
authors: S
authors: Martinez-Miró
authors: Animal Production Department, Veterinary School, Campus of Excellence Mare Nostrum, University of Murcia, Espinardo-Murcia, 30100, Spain.
authors: Fuensanta
authors: F
authors: Hernández
authors: Interdisciplinary Laboratory of Clinical Analysis (Interlab-UMU), Veterinary Clinical Hospital, Campus of Excellence Mare Nostrum, University of Murcia, Espinardo-Murcia, 30100, Spain.|Department of Animal Medicine and Surgery, Veterinary School, University Autonoma of Barcelona, Bellaterra, Barcelona, 08193, Spain.
authors: Asta
authors: A
authors: Tvarijonaviciute
authors: Interdisciplinary Laboratory of Clinical Analysis (Interlab-UMU), Veterinary Clinical Hospital, Campus of Excellence Mare Nostrum, University of Murcia, Espinardo-Murcia, 30100, Spain.
authors: José J
authors: JJ
authors: Cerón
authors: Interdisciplinary Laboratory of Clinical Analysis (Interlab-UMU), Veterinary Clinical Hospital, Campus of Excellence Mare Nostrum, University of Murcia, Espinardo-Murcia, 30100, Spain. ftecles@um.es.
authors: Fernando
authors: F
authors: Tecles
mesh_terms: D000818:Animals; D015153:Blotting, Western / Q000662:veterinary; D015200:Fluoroimmunoassay / Q000379:methods / Q000662:veterinary*; D020738:Leptin / Q000032:analysis*; D012463:Saliva / Q000737:chemistry*; D012680:Sensitivity and Specificity; D013552:Swine
chemical_list: D020738:Leptin
keywords: Inflammation; Leptin; Porcine saliva; Stress; Validation