title: Estimation of restraint stress in rats using salivary amylase activity.
abstract: The rat is an ideal model animal for studying physical and psychological stresses. Recent human studies have shown that salivary amylase activity is a useful biomarker of stress in our social life. To estimate the usefulness of amylase activity as a biomarker of stress in rats, we analyzed changes in physiological parameters including amylase activity and anatomical variables, which were induced by a mild restraint of paws (10 min, 3 times/week, 9 weeks). The quantities of food and water intake  and excretion amount of the stress rats were smaller than those of the control rats during the experimental period (5-13 weeks). The body weight of the stress rats decreased compared with that of the control rats. Moreover, the enlargement of the adrenal gland was confirmed in the stress rats, indicating that the mild restraint caused a chronic stress response. The amylase activities of the stress rats were significantly greater than those of the control rats at 5 weeks of age. However, the amylase activity of the stress rats decreased compared with that of the control rats after 6 weeks of age. These results indicate that amylase activity is increased by acute stress and reduced by chronic stress, which is caused by repeated restraint stress. In conclusion, amylase activity is a useful biomarker of acute and chronic stresses in rats.
authors: Department of Welfare Engineering, Faculty of Engineering, Iwate University, 4-3-5 Ueda, Morioka, 020-8551, Japan. matsuura@iwate-u.ac.jp
authors: Tetsuya
authors: T
authors: Matsuura
authors: Ryo
authors: R
authors: Takimura
authors: Masaki
authors: M
authors: Yamaguchi
authors: Mitsuyuki
authors: M
authors: Ichinose
mesh_terms: D000311:Adrenal Glands / Q000033:anatomy & histology; D000818:Animals; D015415:Biomarkers / Q000032:analysis / Q000378:metabolism; D001835:Body Weight / Q000502:physiology; D003672:Defecation / Q000502:physiology; D004326:Drinking / Q000502:physiology; D004435:Eating / Q000502:physiology / Q000523:psychology; D006854:Hydrocortisone / Q000032:analysis; D008297:Male; D009929:Organ Size; D051381:Rats; D011916:Rats, Inbred F344; D012149:Restraint, Physical / Q000502:physiology*; D055291:Salivary alpha-Amylases / Q000032:analysis / Q000378:metabolism*; D013315:Stress, Psychological / Q000201:enzymology / Q000503:physiopathology*; D014554:Urination / Q000502:physiology
chemical_list: D015415:Biomarkers; D055291:Salivary alpha-Amylases; D006854:Hydrocortisone