Dopamine depresses immunity in the tiger shrimp Penaeus monodon.
The total haemocyte count (THC), differential haemocyte count (DHC), phenoloxidase activity, respiratory bursts (release of superoxide anion), superoxide dismutase activity, phagocytic activity and clearance efficiency to the pathogen Photobacterium damsela were measured when tiger shrimp Penaeus monodon (13.5+/-1.5 g) were individually injected with saline or dopamine at 10(-8), 10(-7), or 10(-6)mol shrimp(-1). Results showed that a transient period of immunosuppression occurred between 2 and 8h after injection of dopamine for all immune parameters except circulating haemocytes, and all immune parameters had returned to control values within 8-16 h after receiving dopamine. The injection of dopamine also significantly increased the mortality of P. monodon challenged with the pathogen Pho. damsela. These results suggest that stress-inducing dopamine suppresses the immune system, which in turn promotes the susceptibility of P. monodon to Pho. damsela.
Chang
Chin-Chyuan
CC
Department of Tropical Agriculture and International Cooperation, National Pingtung University of Science and Technology, 1 Sheuh Fu Road, Nei Pu Hsiang, Pingtung County 91201, Taiwan, ROC.
Wu
Zhi-Rong
ZR
Kuo
Ching-Ming
CM
Cheng
Winton
W
D000818:Animals; D004298:Dopamine / Q000633:toxicity*; D006434:Hemocytes / Q000187:drug effects; D007108:Immune Tolerance / Q000187:drug effects*; D014442:Monophenol Monooxygenase / Q000378:metabolism; D033561:Penaeidae / Q000276:immunology*; D010587:Phagocytosis / Q000187:drug effects; D010776:Photobacterium / Q000276:immunology; D016897:Respiratory Burst / Q000187:drug effects; D013482:Superoxide Dismutase / Q000378:metabolism
D014442:Monophenol Monooxygenase; D013482:Superoxide Dismutase; D004298:Dopamine