Cold-stress induced the modulation of catecholamines, cortisol, immunoglobulin M, and leukocyte phagocytosis in tilapia.
Gen Comp Endocrinol
; 126(1): 90-100, 2002 Mar.
Article
em En
| MEDLINE
| ID: mdl-11944970
ABSTRACT
The concentrations of norepinephrine in hypothalamus and norepinephrine and epinephrine in head kidney were significantly decreased in treated tilapia (Oreochromis aureus) during the time course of cold exposure (12 degrees) as compared to the control (25 degrees). The elevation of norepinephrine and epinephrine in plasma was detected earlier than that of cortisol in cold-treated tilapia. Phagocytic activity of leukocytes and the levels of plasma immunoglobulin M (IgM) were depressed in cold-treated tilapia as compared to the control group. Handling stress in the control (25 degrees) also resulted in increased plasma cortisol and decreased plasma IgM levels but not phagocytic activity. In vitro cortisol suppressed leukocyte phagocytosis in a dose (10(-12) to 10(-4) M)-dependent manner. Adrenergic agonist (phenylephrine and isoproterenol) had a significant suppression of phagocytosis only at the highest dose (10(-4) M). No effect on phagocytosis was detected in the treatment with norepinephrine and epinephrine. A combination of cortisol and isoproterenol (0.1 mM) had an additive effect in the suppression of phagocytosis. It is concluded that the cold stress modulated the changes of catecholamines and cortisol and further depressed phagocytic activity and antibody levels in tilapia. Cortisol could play a main and important role in the down-regulation of phagocytic activity. Adrenergic agonists also could interact with cortisol to further suppress immunity in tilapia.
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Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Imunoglobulina M
/
Hidrocortisona
/
Epinefrina
/
Norepinefrina
/
Tilápia
/
Temperatura Baixa
/
Leucócitos
Limite:
Animals
Idioma:
En
Revista:
Gen Comp Endocrinol
Ano de publicação:
2002
Tipo de documento:
Article
País de afiliação:
China