title: The Choice of Euthanasia Method Affects Metabolic Serum Biomarkers.
abstract: The impact of euthanasia methods on endocrine and metabolic parameters in rodent tissues and biological fluids is highly relevant for the accuracy and reliability of the data collected. However, few studies concerning this issue are found in the literature. We compared the effects of three euthanasia methods currently used in animal experimentation (i.e. decapitation, CO2inhalation and pentobarbital injection) on the serum levels of corticosterone, insulin, glucose, triglycerides, cholesterol and a range of free fatty acids in rats. The corticosterone and insulin levels were not significantly affected by the euthanasia protocol used. However, euthanasia by an overdose of pentobarbital (120 mg/kg intraperitoneal injection) increased the serum levels of glucose, and decreased cholesterol, stearic and arachidonic acids levels compared with euthanasia by CO2inhalation and decapitation. CO2inhalation appears to increase the serum levels of triglycerides, while euthanasia by decapitation induced no individual discrepant biomarker level. We conclude that choice of the euthanasia methods is critical for the reliability of serum biomarkers and indicate the importance of selecting adequate euthanasia methods for metabolic analysis in rodents. Decapitation without anaesthesia may be the most adequate method of euthanasia when taking both animal welfare and data quality in consideration.
authors.affiliation: Department of Pharmaceutical Biosciences, Uppsala University, Uppsala, Sweden.
authors.forename: Paula
authors.initials: P
authors.lastname: Pierozan
authors.affiliation: Department of Pharmaceutical Biosciences, Uppsala University, Uppsala, Sweden.
authors.forename: Fredrik
authors.initials: F
authors.lastname: Jernerén
authors.affiliation: Department of Social and Behavioral Sciences, Harvard T.H. Chan School of Public Health, Boston, MA, USA.
authors.forename: Yusuf
authors.initials: Y
authors.lastname: Ransome
authors.affiliation: Department of Pharmaceutical Biosciences, Uppsala University, Uppsala, Sweden.|Department of Clinical Neuroscience, Center for Molecular Medicine, Karolinska Institute, Stockholm, Sweden.
authors.forename: Oskar
authors.initials: O
authors.lastname: Karlsson
mesh_terms: D000818:Animals; D000830:Animals, Laboratory; D001237:Asphyxia / Q000097:blood; D015415:Biomarkers / Q000097:blood*; D035843:Biomedical Research / Q000379:methods*; D002245:Carbon Dioxide / Q000506:poisoning; D049248:Decapitation / Q000097:blood; D037901:Euthanasia, Animal; D005260:Female; D006993:Hypnotics and Sedatives / Q000506:poisoning; D010424:Pentobarbital / Q000506:poisoning; D017208:Rats, Wistar; D015203:Reproducibility of Results; D044967:Serum / Q000737:chemistry*
chemical_list: D015415:Biomarkers; D006993:Hypnotics and Sedatives; D002245:Carbon Dioxide; D010424:Pentobarbital