title: Systemic prostacyclin and thromboxane production in obstructive sleep apnea.
abstract: OBJECTIVE
  Obstructive sleep apnea increases the risk of cardiovascular diseases. Alternations in prostacyclin and thromboxane concentrations and balance could constitute one of mechanisms linking sleep apnea and cardiovascular events. Thus we aimed to assess the concentrations of 6-keto-prostaglandin F1α (6-keto-PGF1α) (metabolite of prostacyclin) and thromboxane B2 (TXB2) (metabolite of thromboxane A2) in urine and blood of obstructive sleep apnea patients and controls (snoring subjects with otherwise normal polysomnogram).
  
  
  METHODS
  Overnight urine and morning blood samples were taken from subjects and controls at baseline and in sleep apnea group during continuous positive airway pressure (CPAP) treatment. Samples were analyzed using mass chromatography/gas spectrometry.
  
  
  RESULTS
  We analyzed data from 26 obstructive sleep apnea subjects (mean apnea-hypopnea index 45.4±17.3) and 22 well-matched controls. At baseline sleep apnea patients, when compared to controls, have higher 6-keto-PGF1α in urine (0.89±0.15 vs 0.34±0.06, p=0.01) and blood (24.49±1.54 vs 19.70±1.77, p=0.04). TXB2 levels in urine and blood were not different across groups. CPAP treatment significantly decreased 6-keto-PGF1α in urine (0.92±0.17 vs 0.22±0.10, p=0.04), but not in blood. TXB2 levels during CPAP treatment did not change significantly.
  
  
  CONCLUSIONS
  These results suggest augmented systemic prostacyclin production in obstructive sleep apnea patients, which potentially could constitute a protective mechanism against detrimental effects of sleep apnea.
authors.affiliation: II Department of Internal Medicine, Jagiellonian University Medical College, Cracow, Poland. Electronic address: filipmejza@mp.pl.
authors.forename: Filip
authors.initials: F
authors.lastname: Mejza
authors.affiliation: Division of Lung Diseases, Jagiellonian University Medical College, Cracow, Poland.
authors.forename: Aleksander
authors.initials: A
authors.lastname: Kania
authors.affiliation: II Department of Internal Medicine, Jagiellonian University Medical College, Cracow, Poland.
authors.forename: Pawel
authors.initials: P
authors.lastname: Nastalek
authors.affiliation: Department of Orthodontics, Jagiellonian University Medical College, Cracow, Poland.
authors.forename: Agata
authors.initials: A
authors.lastname: Nizankowska-Jedrzejczyk
authors.affiliation: Division of Lung Diseases, Jagiellonian University Medical College, Cracow, Poland.
authors.forename: Ewa
authors.initials: E
authors.lastname: Nizankowska-Mogilnicka
mesh_terms: D015121:6-Ketoprostaglandin F1 alpha / Q000097:blood / Q000652:urine; D000328:Adult; D000368:Aged; D016022:Case-Control Studies; D045422:Continuous Positive Airway Pressure; D011464:Epoprostenol / Q000096:biosynthesis*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D020181:Sleep Apnea, Obstructive / Q000097:blood / Q000378:metabolism* / Q000652:urine; D013929:Thromboxane B2 / Q000097:blood / Q000652:urine; D013931:Thromboxanes / Q000096:biosynthesis*
chemical_list: D013931:Thromboxanes; D013929:Thromboxane B2; D015121:6-Ketoprostaglandin F1 alpha; D011464:Epoprostenol
keywords: Continuous positive airway pressure; Obstructive sleep apnea; Prostacyclin; Thromboxane