Diurnal behavioral and endocrine effects of chronic shaker stress in mice.
Neuro Endocrinol Lett
; 28(6): 846-53, 2007 Dec.
Article
em En
| MEDLINE
| ID: mdl-18063939
ABSTRACT
Experiments were performed in C57BL/6J male mice to determine 1) light/dark effects of acute and chronic shaker stress on open field behavioral patterns and 2) light/dark effects of chronic stress on plasma corticosterone and oxytocin. Shaker stress was applied acutely (15 min) or chronically (3 or 7 days). Mice were tested in the open field in the light or dark phase of the circadian cycle. For the endocrine study, mice were exposed to 3 days of intermittent shaker stress and sacrificed after the last stress event (0900 or 1900 h). Acute or chronic shaker stress had no significant effects on intensity of motor activity and rearing of mice tested under either light condition. Mice tested in the dark phase had higher motor activity and exhibited lower anxiety-like behavior as expressed by central zone activities and had higher emotionality as expressed by increased defecation. Chronic stress increased corticosterone with a greater absolute increase in the dark period. However, the percentage stress-induced increase was not different between the day and night periods. The oxytocin response to stress was observed only during the light phase with no change seen at dark phase. These results show that there is a marked difference in the light/dark pituitary stress response with no alteration in stress induced behavioral changes. They also suggest that there are circadian interactions in the endocrine stress axis that are without consequences for open field behavior.
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Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Estresse Fisiológico
/
Corticosterona
/
Ocitocina
/
Ritmo Circadiano
/
Comportamento Exploratório
Tipo de estudo:
Etiology_studies
Limite:
Animals
Idioma:
En
Revista:
Neuro Endocrinol Lett
Ano de publicação:
2007
Tipo de documento:
Article