title: Modulation of chicken plaque-forming cells by serotonin and dopamine.
abstract: Serotonin (5-hydroxytryptamine, 5-HT) and dopamine (DA) are endogenous components of the central nervous and endocrine systems of the chicken. To determine the effects of these monoamines on antibody-mediated immunity. New Hampshire chickens of Line UNH 105 were injected intravenously with 5-HT (100 micrograms/kg of body weight) and DA (1 mg/kg of body weight). One milliliter of a 5% SRBC suspension was injected intravenously 30 min later. Both IgM and IgG splenic plaque-forming cells were assayed 5 days after antigen injection. For in vitro studies, spleen lymphocytes from SRBC-primed chicks were incubated with DA and 5-HT followed by quantitation of IgM and IgG plaque-forming cells. The in vivo incubation of splenic lymphocytes with specific antagonists was used to ascertain the presence of monoamine receptors on lymphocytes. The 5-HT significantly enhanced IgM plaque-forming cells compared with controls following in vivo [550 +/- 85 (SE) cells/10(6) splenic lymphocytes versus 359 +/- 44] but not in vitro exposure. The IgG plaque-forming cells were not affected by 5-HT. The DA significantly suppressed IgM plaque-forming cells responses following in vivo (284 +/- 46 versus 499 +/- 66) and in vitro (254 +/- 57 versus 451 +/- 51) exposure. Significant suppression of IgG plaque-forming cells was found in vivo (287 +/- 40 versus 462 +/- 75) and in vitro (153 +/- 36 versus 371 +/- 81) following treatment. Specific DA antagonists, apomorphine and metoclopramide, did not alleviate the in vitro suppressive effect of DA.
authors.affiliation: Department of Biology, Central Michigan University, Mt. Pleasant 48859.
authors.forename: R S
authors.initials: RS
authors.lastname: Gray
authors.forename: F M
authors.initials: FM
authors.lastname: McCorkle
authors.forename: K M
authors.initials: KM
authors.lastname: Denno
authors.forename: R L
authors.initials: RL
authors.lastname: Taylor
mesh_terms: D000818:Animals; D002645:Chickens / Q000276:immunology*; D004298:Dopamine / Q000494:pharmacology*; D005260:Female; D007074:Immunoglobulin G / Q000276:immunology; D007075:Immunoglobulin M / Q000276:immunology; D007958:Leukocyte Count / Q000662:veterinary; D008214:Lymphocytes / Q000187:drug effects* / Q000276:immunology; D008297:Male; D012701:Serotonin / Q000494:pharmacology*; D013154:Spleen / Q000166:cytology*
chemical_list: D007074:Immunoglobulin G; D007075:Immunoglobulin M; D012701:Serotonin; D004298:Dopamine