Response of rats to the presence of stressed conspecifics as a function of time of day.
The physiological response of nonrestrained rats to the presence of immobilized conspecifics during the beginning of the active period and the inactive period was studied. In immobilized animals concentrations of serum corticosterone (SCS), serum glucose, and liver glycogen, and the activity of liver tyrosine aminotransferase (TAT) during both the active and the inactive periods, were consistent with earlier studies. In nonrestrained rats the presence of immobilized conspecifics induced a significant increase in SCS during the active period, whereas it had no effect during the inactive period. The level of TAT was significantly elevated in the nonrestrained rats only during the inactive period and remained unchanged during the active period. The results demonstrate a physiological influence of stressed rats on unstressed conspecifics and provide evidence for regulation of TAT activity that is dependent on the situation and the time of day.
D000204:Activity Cycles; D000818:Animals; D001786:Blood Glucose / Q000032:analysis; D002940:Circadian Rhythm; D003345:Corticosterone / Q000097:blood; D006003:Glycogen / Q000032:analysis; D007103:Immobilization; D008099:Liver / Q000032:analysis / Q000201:enzymology; D008297:Male; D051381:Rats; D011919:Rats, Inbred Strains; D013312:Stress, Physiological / Q000503:physiopathology*; D014444:Tyrosine Transaminase / Q000378:metabolism
D001786:Blood Glucose; D006003:Glycogen; D014444:Tyrosine Transaminase; D003345:Corticosterone