Effects of social conflict on immune responses and E. coli growth within closed chambers in mice.
Physiol Behav
; 67(1): 133-40, 1999 Aug 01.
Article
em En
| MEDLINE
| ID: mdl-10463639
ABSTRACT
Social conflict has been shown to affect the neuroendocrine stress response in rodents. The current study was designed to characterize the effects of social conflict on leukocyte subset distribution and function as well as in vivo bacterial growth. Male DBA/2 mice implanted or not implanted with a closed chamber containing Escherichia coli were repeatedly challenged by temporary placement in the territory of a dominant CF-1 mouse five times a day for 2 consecutive days. Nonstressed animals were similarly handled, but were not exposed to social conflict. Effects on immune responses and E. coli growth were analyzed 13 h after the last social conflict session. Social conflict alone was associated with an increase in plasma corticosterone concentration and decreases in thymocyte numbers and splenocyte ability to proliferate in vitro in the presence of lipopolysaccharide (p < 0.05). After social conflict, immature CD4+CD8+ thymocytes decreased, whereas mature T cells increased (p < 0.05). In the presence of E. coli, social conflict induced a significant increase in plasma concentration of interleukin-1beta, and a decrease in the number of thymocytes and the percentage of CD4+CD8+ T cells in the thymus (p < 0.05). In addition to the lymphocyte subpopulation changes observed with social conflict alone, the proportion of CD3+ and major histocompatibility complex (MHC) class II IAd+ cells were significantly higher in stressed mice implanted with a closed chamber containing E. coli (p < 0.05). Social conflict tended to favor E. coli growth in the closed chamber, indicating possible direct bacterial-neuroendocrine hormone interactions. Taken together, these results suggest that stress may modulate the host immune response by altering both bacterial growth and resistance to infection.
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Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Nível de Alerta
/
Conflito Psicológico
/
Escherichia coli O157
/
Dominação-Subordinação
Limite:
Animals
Idioma:
En
Revista:
Physiol Behav
Ano de publicação:
1999
Tipo de documento:
Article
País de afiliação:
Estados Unidos