title: Increased norepinephrine variability in patients with sleep apnea syndrome.
abstract: OBJECTIVE
  To assess the plasma arterial catecholamine response to nocturnal desaturation in a group of patients with a history suggestive of sleep apnea.
  
  
  METHODS
  At a Veterans Affairs hospital, 10 patients who had a history consistent with sleep apnea syndrome were involved in the study. Arterial plasma catecholamines were measured at varying intervals during a 5 1/2-hour sleep study. Eighteen samples per patient were analyzed.
  
  
  RESULTS
  As the hemoglobin saturation decreased, the variability in plasma norepinephrine increased significantly (r = -.78, P = 0.004). As the hemoglobin saturation fell, there was a trend towards higher concentrations of plasma norepinephrine (r = -.53, P = 0.06). As the hemoglobin saturation decreased, the variability in plasma epinephrine concentration was not significant (r = .42).
  
  
  CONCLUSIONS
  The association between the degree of desaturation and the variability in norepinephrine suggests that norepinephrine is released in response to nocturnal desaturation.
authors.affiliation: Veterans Affairs Medical Center, Fresno, California 93703, USA.
authors.forename: P
authors.initials: P
authors.lastname: Baylor
authors.forename: A
authors.initials: A
authors.lastname: Mouton
authors.forename: H H
authors.initials: HH
authors.lastname: Shamoon
authors.forename: P
authors.initials: P
authors.lastname: Goebel
mesh_terms: D000328:Adult; D000368:Aged; D002245:Carbon Dioxide / Q000097:blood; D006454:Hemoglobins / Q000378:metabolism; D006801:Humans; D008875:Middle Aged; D009638:Norepinephrine / Q000097:blood*; D010092:Oximetry; D010100:Oxygen / Q000097:blood; D017286:Polysomnography; D012129:Respiratory Function Tests; D012891:Sleep Apnea Syndromes / Q000097:blood*; D013997:Time Factors
chemical_list: D006454:Hemoglobins; D002245:Carbon Dioxide; D010100:Oxygen; D009638:Norepinephrine