title: A fluid response: Alpha-amylase reactions to acute laboratory stress are related to sample timing and saliva flow rate.
abstract: Salivary alpha-amylase (sAA) is used as a sympathetic (SNS) stress marker, though its release is likely co-determined by SNS and parasympathetic (PNS) activation. The SNS and PNS show asynchronous changes during acute stressors, and sAA responses may thus vary with sample timing. Thirty-four participants underwent an eight-minute memory task (MT) and cold pressor task (CPT). Cardiovascular SNS (pre-ejection period, blood pressure) and PNS (heart rate variability) activity were monitored continuously. Unstimulated saliva was collected repeatedly during and after each laboratory stressor, and sAA concentration (U/ml) and secretion (U/minute) determined. Both stressors increased anxiety. The MT caused an immediate and continued cardiac SNS activation, but sAA concentration increased at task cessation only (+54%); i.e., when there was SNS-PNS co-activation. During the MT sAA secretion even decreased (-35%) in conjunction with flow rate and vagal tone. The CPT robustly increased blood pressure but not sAA. In summary, sAA fluctuations did not parallel changes in cardiac SNS activity or anxiety. sAA responses seem contingent on sample timing and flow rate, likely involving both SNS and PNS influences. Verification using other stressors and contexts seems warranted.
authors.affiliation: Department of Clinical Psychology, University of Amsterdam, Weesperplein 4, 1018 XA, Amsterdam, the Netherlands; Doctoral School of Psychology, Education and Psychology, Eötvös Loránd University, Izabella u. 46, 1064, Budapest, Hungary. Electronic address: nagy.tamas@ppk.elte.hu.
authors.forename: Tamás
authors.initials: T
authors.lastname: Nagy
authors.affiliation: Department of Biological Psychology, VU University, Van der Boechorststraat 1, 1081 BT, Amsterdam, the Netherlands.
authors.forename: René
authors.initials: R
authors.lastname: van Lien
authors.affiliation: Department of Biological Psychology, VU University, Van der Boechorststraat 1, 1081 BT, Amsterdam, the Netherlands.
authors.forename: Gonneke
authors.initials: G
authors.lastname: Willemsen
authors.affiliation: Mucosal & Salivary Biology Division, King's College London Floor 17, Guy's Tower Guy's Hospital London SE1 9RT UK.
authors.forename: Gordon
authors.initials: G
authors.lastname: Proctor
authors.affiliation: Department of Clinical Psychology, University of Amsterdam, Weesperplein 4, 1018 XA, Amsterdam, the Netherlands.
authors.forename: Marieke
authors.initials: M
authors.lastname: Efting
authors.affiliation: Institute for Cognitive Neuroscience and Psychology, Research Centre of Natural Sciences, Hungarian Academy of Sciences, Magyar Tudósok körútja 2, Budapest H-1117, Hungary.
authors.forename: Márta
authors.initials: M
authors.lastname: Fülöp
authors.affiliation: Institute of Health Promotion and Sport Sciences, Bogdánffy Ödön u. 10, Budapest, H-1117, Hungary.
authors.forename: György
authors.initials: G
authors.lastname: Bárdos
authors.affiliation: Department of Oral Biochemistry, Academic Centre of Dentistry (ACTA), Gustav Mahlerlaan 3004, 1081 LA, Amsterdam, The Netherlands.
authors.forename: Enno C I
authors.initials: EC
authors.lastname: Veerman
authors.affiliation: Department of Clinical Psychology, University of Amsterdam, Weesperplein 4, 1018 XA, Amsterdam, the Netherlands; Mannheim Institute of Public Health, Social and Preventive Medicine (MIPH), University of Heidelberg, Ludolf-Krehl-Straße 7-11, D-68167, Mannheim, Germany. Electronic address: J.A.Bosch@uva.nl.
authors.forename: Jos A
authors.initials: JA
authors.lastname: Bosch
mesh_terms: D000328:Adult; D001794:Blood Pressure / Q000502:physiology; D005260:Female; D006339:Heart Rate / Q000502:physiology; D006801:Humans; D008297:Male; D010275:Parasympathetic Nervous System / Q000502:physiology*; D012463:Saliva / Q000737:chemistry / Q000378:metabolism*; D055291:Salivary alpha-Amylases / Q000378:metabolism*; D013315:Stress, Psychological / Q000378:metabolism* / Q000503:physiopathology*; D013564:Sympathetic Nervous System / Q000502:physiology*; D055815:Young Adult
chemical_list: D055291:Salivary alpha-Amylases
keywords: Acute stress; Alpha-amylase; Parasympathetic nervous system; Saliva; Salivary flow rate; Sympathetic nervous system