title: Role of nitric oxide in alcohol alteration of beta-endorphin release from hypothalamic cells in primary cultures.
abstract: BACKGROUND
  Nitric oxide (NO) mediates many pharmacological actions of ethanol. NO's role in regulating ethanol action on hypothalamic beta-endorphin (beta-EP) neurons is not established.
  
  
  METHODS
  In this study, we determined the role of NO in ethanol regulation of beta-EP release from primary cultures of rat fetal mediobasal hypothalamic cells. Real-time polymerase chain reaction was used for messenger RNA (mRNA) detection; radioimmunoassay was used for hormone measurements.
  
  
  RESULTS
  Acute ethanol treatment for 3 hr increased the release of beta-EP but reduced nitrite levels in the media of hypothalamic cells in primary cultures. In contrast, ethanol exposure for 48 hr reduced the release of beta-EP but increased the release of nitrite from these cells. Alcohol treatments altered the expression of neuronal NO synthase mRNA, but not inducible NO synthase mRNA, in a pattern similar to that of nitrite levels. Alcohol treatments blocked sodium nitroprusside-induced increases in the level of cellular cyclic guanidine monophosphate. The nonspecific NO blocker NG-nitro-l-arginine-methyl-esther, but not the inactive isomer N-nitro-d-arginine-methyl-esther (d-NAME), inhibited ethanol inhibitory actions on beta-EP release.
  
  
  CONCLUSIONS
  These results suggest that the cyclic guanidine monophosphate/NO pathway is involved in ethanol alteration of hypothalamic beta-EP release.
authors.affiliation: Center for Alcohol Studies and Department of Animal Sciences, Rutgers, The State University of New Jersey, New Brunswick 08901-8525, USA.
authors.forename: Nadka I
authors.initials: NI
authors.lastname: Boyadjieva
authors.forename: Cui P
authors.initials: CP
authors.lastname: Chen
authors.forename: Dipak K
authors.initials: DK
authors.lastname: Sarkar
mesh_terms: D000818:Animals; D002478:Cells, Cultured; D004305:Dose-Response Relationship, Drug; D000431:Ethanol / Q000494:pharmacology*; D007031:Hypothalamus / Q000187:drug effects* / Q000378:metabolism*; D009569:Nitric Oxide / Q000502:physiology*; D051381:Rats; D001615:beta-Endorphin / Q000378:metabolism*
chemical_list: D009569:Nitric Oxide; D000431:Ethanol; D001615:beta-Endorphin