title: [Effect of acetylcholine on the cytotoxicity of natural killer cells].
abstract: OBJECTIVE
  To investigate the effect of acetylcholine (ACh) on the cytotoxicity of natural killer (NK) cells and to explore the receptor mechanisms involved in the effect.
  
  
  METHODS
  The effector cells (i. e. NK cells) from the spleens of rats were collected and cultured with the target cells (Yac-1 cells). The various concentrations of ACh, cholinergic receptor agonists or antagonists were added to the cultures, respectively according to distinct experimental purposes. Lactate dehydrogenase (LDH) release assay was used to evaluate NK cell cytotoxicity.
  
  
  RESULTS
  NK-cell-mediated lysis of Yac-1 lymphoma cells was reduced by 10(-10) - 10(-6) mol/L ACh. The inhibitory effect of ACh on NK cell cytotoxicity was mimicked by pilocarpine, an agonist of muscarinic receptor, and by nicotine, an agonist of nicotinic receptor, at all applied concentrations (10(-10) - 10(-6) mol/L). Muscarinic receptor antagonist atropine blocked the inhibitory effect of ACh on the cytotoxicity of NK cells. Nevertheless, tubocurarine, an antagonist of nicotinic receptor, had no blocking effect on the suppression of NK cell cytotoxicity by ACh.
  
  
  CONCLUSIONS
  ACh results in an inhibition of the cytotoxicity of NK cells, and this inhibition is realized mainly through M and N1 cholinergic receptor.
authors.affiliation: Department of Physiology, School of Basic Medical Sciences, Nantong University, Nantong 226001, China.
authors.forename: Jian-Lan
authors.initials: JL
authors.lastname: Jiang
authors.forename: Yi-Hua
authors.initials: YH
authors.lastname: Qiu
authors.forename: Yu-Ping
authors.initials: YP
authors.lastname: Peng
mesh_terms: D000109:Acetylcholine / Q000494:pharmacology*; D000818:Animals; D002478:Cells, Cultured; D005260:Female; D007694:Killer Cells, Natural / Q000166:cytology / Q000187:drug effects* / Q000276:immunology*; D008297:Male; D051381:Rats; D055607:Receptors, Natural Killer Cell / Q000187:drug effects
chemical_list: D055607:Receptors, Natural Killer Cell; D000109:Acetylcholine