title: Salivary chromogranin A, but not α-amylase, correlates with cardiovascular parameters during high-intensity exercise.
abstract: BACKGROUND
  Several studies have shown that activation of the sympathetic nervous system results in the increased secretion of α-amylase (sAA), an enzyme produced by salivary glands. Recently, chromogranin A (CgA), a soluble protein costored and coreleased with catecholamines from the adrenal medulla and sympathetic nerve endings, has been proposed as a marker of sympathoadrenal medullary system (SAM) activity. The aim of this study was to investigate the behaviour of salivary chromogranin A (sCgA) and sAA during high-intensity exercise and to analyse their possible correlation with cardiovascular and psychological parameters.
  
  
  METHODS
  Before and during a standardized treadmill stress test, and at 5, 15 and 30 min during the recovery phase, sCgA and sAA were monitored in 21 healthy men. The double product (DP) of blood pressure and heart rate responses, and the product of the subjective ratings of perceived exertion recorded at the final step (RPE) and the exercise duration were used as indices of cardiovascular and exercise intensity, respectively.
  
  
  RESULTS
  With respect to baseline, significant (P < 0·001) increases in peak sCgA (median 64%) and sAA (median 86%) were observed at the end of exercise. During the recovery phase, sAA levels fell abruptly, whereas sCgA remained elevated (P < 0·001). Significant correlations emerged only for sCgA with respect to %DP (r = 0·84; P < 0·001) and last step-RPE (r = 0·82; P = 0·024).
  
  
  CONCLUSIONS
  These data suggest sCgA as a reliable marker of SAM activation. Furthermore, the relationship between sCgA and exercise intensity highlights the potential use of this noninvasive parameter in monitoring the adrenergic response during intense physical stress.
authors.affiliation: Department of Human Movement, University G. D'Annunzio, Chieti - Pescara, Italy.
authors.forename: Sabina
authors.initials: S
authors.lastname: Gallina
authors.forename: Michele
authors.initials: M
authors.lastname: Di Mauro
authors.forename: Maria Angela
authors.initials: MA
authors.lastname: D'Amico
authors.forename: Emanuele
authors.initials: E
authors.lastname: D'Angelo
authors.forename: Andrea
authors.initials: A
authors.lastname: Sablone
authors.forename: Alessia
authors.initials: A
authors.lastname: Di Fonso
authors.forename: Adriana
authors.initials: A
authors.lastname: Bascelli
authors.forename: Pascal
authors.initials: P
authors.lastname: Izzicupo
authors.forename: Angela
authors.initials: A
authors.lastname: Di Baldassarre
mesh_terms: D000328:Adult; D002320:Cardiovascular Physiological Phenomena; D002319:Cardiovascular System / Q000378:metabolism; D053379:Chromogranin A / Q000032:analysis / Q000378:metabolism*; D015444:Exercise / Q000502:physiology*; D005080:Exercise Test; D006801:Humans; D008297:Male; D005082:Physical Exertion / Q000502:physiology; D012463:Saliva / Q000737:chemistry / Q000201:enzymology / Q000378:metabolism*; D013048:Specimen Handling; D055815:Young Adult; D000516:alpha-Amylases / Q000032:analysis / Q000378:metabolism*
chemical_list: D053379:Chromogranin A; D000516:alpha-Amylases