Lifetime Dependent Variation of Stress Hormone Metabolites in Feces of Two Laboratory Mouse Strains.
Non-invasive measurement of stress hormone metabolites in feces has become routine practice for the evaluation of distress and pain in animal experiments. Since metabolism and excretion of glucocorticoids may be variable, awareness and adequate consideration of influencing factors are essential for accurate monitoring of adrenocortical activity. Reference values are usually provided by baselines compiled prior to the experiment and by age matched controls. The comparison of stress hormone levels between animals of different ages or between studies looking at hormone levels at the beginning and at the end of a long term study might be biased by age-related effects. In this study we analyzed fecal corticosterone metabolites (FCM) during the lifetime of untreated female mice of the strains C57BL/6NCrl and Crl:CD1. For this purpose feces for each individual mouse were collected every two months over a period of 24 hours, at intervals of four hours, until the age of 26 months. Results of the study revealed that age of the animals had a significant impact on the level and circadian rhythm of stress hormone metabolites. Furthermore, long-term observation of mice revealed a strain specific excretion profile of FCM influenced by strong seasonal variability.
Biomodels Austria, University of Veterinary Medicine Vienna, Vienna, Austria; IFA-Tulln, University of Natural Resources and Life Sciences, Tulln, Austria.
Thomas
T
Kolbe
Unit of Physiology, Pathophysiology and Experimental Endocrinology, University of Veterinary Medicine Vienna, Vienna, Austria.
Rupert
R
Palme
Bioinformatics and Biostatistics Platform, University of Veterinary Medicine Vienna, Vienna, Austria.
Alexander
A
Tichy
Institute of Laboratory Animal Science, University of Veterinary Medicine Vienna, Vienna, Austria.
Thomas
T
Rülicke
D000818:Animals; D002940:Circadian Rhythm / Q000502:physiology*; D003345:Corticosterone / Q000378:metabolism*; D005243:Feces / Q000737:chemistry*; D005260:Female; D051379:Mice; D008810:Mice, Inbred C57BL; D013045:Species Specificity; D013312:Stress, Physiological; D013997:Time Factors
D003345:Corticosterone