title: Dopamine depresses the immune ability and increases susceptibility to Lactococcus garvieae in the freshwater giant prawn, Macrobrachium rosenbergii.
abstract: The total haemocyte count (THC), phenoloxidase activity, respiratory burst (release of superoxide anion), superoxide dismutase activity, and phagocytic activity and clearance efficiency to the pathogen Lactococcus garvieae were measured when freshwater giant prawns Macrobrachium rosenbergii (16.2 +/- 2.1 g) were individually injected with saline, or dopamine at 0.5, 5.0, or 50.0 pmol prawn(-1). The results show that a transient period of immunosuppression occurred between 2 and 8 h after injection of dopamine for all immune parameters except circulating haemocytes and all immune parameters returned to control values within 8-16 h after receiving dopamine. Injection of dopamine also significantly increased the mortality of M. rosenbergii challenged with the pathogen L. garvieae. These results suggest that stress-inducing dopamine suppresses the immune system, which in turn promotes the susceptibility to L. garvieae in M. rosenbergii.
authors.affiliation: Department of Aquaculture, National Pingtung University of Science and Technology, Taiwan.
authors.forename: Jian-Tong
authors.initials: JT
authors.lastname: Li
authors.forename: Pai-Po
authors.initials: PP
authors.lastname: Lee
authors.forename: Ou-Chuan
authors.initials: OC
authors.lastname: Chen
authors.forename: Winton
authors.initials: W
authors.lastname: Cheng
authors.forename: Ching-Ming
authors.initials: CM
authors.lastname: Kuo
mesh_terms: D000818:Animals; D000917:Antibody Formation / Q000187:drug effects*; D001772:Blood Cell Count; D004298:Dopamine / Q000494:pharmacology*; D004305:Dose-Response Relationship, Drug; D005618:Fresh Water; D007111:Immunity, Cellular / Q000187:drug effects*; D017045:Lactococcus; D014442:Monophenol Monooxygenase / Q000378:metabolism; D033541:Palaemonidae / Q000276:immunology* / Q000382:microbiology*; D010587:Phagocytosis / Q000187:drug effects; D016897:Respiratory Burst / Q000187:drug effects; D013482:Superoxide Dismutase / Q000378:metabolism; D013997:Time Factors
chemical_list: D014442:Monophenol Monooxygenase; D013482:Superoxide Dismutase; D004298:Dopamine