title: Phenol-containing saline solution as a diluent for adenosine 5'-monophosphate in bronchial challenge testing.
abstract: OBJECTIVE
  To investigate the effect of dissolving adenosine 5'-monophosphate (AMP) with phenol-containing saline solution on the stability and the bronchoconstrictive properties of this indirect agonist.
  
  
  METHODS
  Eleven subjects with asthma well controlled with short-acting inhaled beta2-agonists as required or with inhaled corticosteroids were studied. Bronchial challenge tests with AMP dissolved with either normal saline solution or saline solution containing 0.4% phenol were performed on separate days. Furthermore, to assess the potential influence of the phenol-containing saline solution on the stability of the bronchoconstrictor agent, AMP solutions in concentrations of 40 microg/mL and 400 microg/mL were prepared in saline solution and phenol-containing saline solution and, after 30 min, the AMP levels were determined by high-performance liquid chromatography (HPLC) assay.
  
  
  RESULTS
  The geometric mean AMP provocative concentration causing a 20% fall in FEV1 (PC20) was 13.49 mg/mL (95% confidence interval [CI], 6.76 to 26.91) for the saline solution method, and AMP PC20 for the saline solution with phenol method was 8.91 mg/mL (95% CI, 3.39 to 23.44) [p = 0.18]. No significant differences were found between the concentrations of AMP made in saline solution compared to those made in phenol-containing saline solution measured by HPLC.
  
  
  CONCLUSIONS
  These observations indicate that normal saline solution with or without phenol can be used as the diluent for AMP. However, since a potential risk with AMP of industrial sources is the bacterial contamination, adding a preservative such as phenol to a saline solution diluent might be recommended.
authors.affiliation: Sección de Alergología, Hospital Universitario Dr Peset, Valencia, Spain. prieto_jes@gva.es
authors.forename: Luis
authors.initials: L
authors.lastname: Prieto
authors.forename: Carlos
authors.initials: C
authors.lastname: Badiola
authors.forename: Julio
authors.initials: J
authors.lastname: Cortijo
authors.forename: Carmen
authors.initials: C
authors.lastname: Pérez-Francés
authors.forename: Valentina
authors.initials: V
authors.lastname: Gutiérrez
authors.forename: Amparo
authors.initials: A
authors.lastname: Lanuza
mesh_terms: D000249:Adenosine Monophosphate / Q000008:administration & dosage* / Q000737:chemistry; D000280:Administration, Inhalation; D000328:Adult; D001249:Asthma / Q000175:diagnosis*; D001985:Bronchial Provocation Tests; D002851:Chromatography, High Pressure Liquid; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010636:Phenols / Q000032:analysis; D012965:Sodium Chloride / Q000737:chemistry
chemical_list: D010636:Phenols; D000249:Adenosine Monophosphate; D012965:Sodium Chloride