Alpha-amylase
Alpha-amylase is a hormone that controls the autonomic nervous system (sympathetic / parasympathetic). In its importance for the autonomic nervous system, it corresponds to that of cortisol for the HPA axis.
Alpha-amylase levels correlate with changes in cortisol levels.1
α-Amylase is secreted from the parotid gland (parotid gland, parotid gland or parotid gland) during adrenergic activity. α-Amylase is a marker of stress-induced adrenergic activity2 and of mean arterial pressure (MAP). Mean arterial pressure is the product of cardiac output and total peripheral resistance, reflecting organ perfusion. It represents a physiological measure of sympathetic activation.3
α-Amylase increases more rapidly than salivary cortisol during psychosocial stress.4 It is possible that only salivary alpha-amylase, but not blood alpha-amylase levels, are increased in response to an acute stressor, whereas both blood and salivary alpha-amylase levels respond in unison to pharmacological treatment. These differences do not exist for cortisol.
Alpha-amylase stress response is significantly increased in subjects with childhood trauma.5
Of 62 ADHD-affected children, the ADHD-HI type showed an identical cortisol level before venipuncture as nonaffected individuals, whereas the ADHD-I subtype showed an elevated cortisol level even before venipuncture compared with nonaffected individuals. Since basal cortisol levels are lower in both ADHD-I and ADHD-HI affected individuals than in nonaffected individuals, this could be an anxiety response in anticipation of the stressor.1 The same pattern was shown with respect to alpha-amylase as a representative of the vegetative nervous system.
Prolonged treatment with stimulants reduces cortisol and alpha-amylase levels in ADHD sufferers.6
The basal alpha-amylase progression corresponds to that of cortisol.
In boys with externalizing problems, basal cortisol levels also follow the typical (decreasing) diurnal course, sometimes starting from a lower morning level. In contrast, oppositional defiant behavior (ODD) or ADHD do not influence the cortisol diurnal course.7
However, externalizing behavior disorders in boys correlated with significantly decreased alpha-amylase levels.7
Subjects with a COMT Val158Val or a Met158Met gene polymorphism showed lower alpha-amylase levels than subjects with a COMT Val158Met gene polymorphism.7
Angeli, Korpa, Johnson, Apostolakou, Papassotiriou, Chrousos, Pervanidou (2018):Salivary cortisol and alpha-amylase diurnal profiles and stress reactivity in children with Attention Deficit Hyperactivity Disorder. Psychoneuroendocrinology. 2018 Apr;90:174-181. doi: 10.1016/j.psyneuen.2018.02.026. ↥ ↥
van Stegeren, Rohleder, Everaerd, Wolf (2006): Salivary alpha amylase as marker for adrenergic activity during stress: effect of betablockade. Psychoneuroendocrinology. 2006 Jan;31(1):137-41. doi: 10.1016/j.psyneuen.2005.05.012. PMID: 16046076. ↥
Bloomfield, McCutcheon, Kempton, Freeman, Howes (2019): The effects of psychosocial stress on dopaminergic function and the acute stress response. Elife. 2019 Nov 12;8:e46797. doi: 10.7554/eLife.46797. PMID: 31711569; PMCID: PMC6850765. ↥
Maruyama, Kawano, Okamoto, Ando, Ishitobi, Tanaka, Inoue, Imanaga, Kanehisa, Higuma, Ninomiya, Tsuru, Hanada, Akiyoshi (2012): Differences in salivary alpha-amylase and cortisol responsiveness following exposure to electrical stimulation versus the Trier Social Stress Tests. PLoS One. 2012;7(7):e39375. doi: 10.1371/journal.pone.0039375. PMID: 22859941; PMCID: PMC3408464. ↥
Kuras, McInnis, Thoma, Chen, Hanlin, Gianferante, Rohleder (2016): Increased alpha-amylase response to an acute psychosocial stress challenge in healthy adults with childhood adversity. Dev Psychobiol. 2017 Jan;59(1):91-98. doi: 10.1002/dev.21470. ↥
Ertugrul, Kirzioglu, Aktepe, Savas (2018): The effects of psychostimulants on oral health and saliva in children with attention deficit hyperactivity disorder: A case-control study. Niger J Clin Pract. 2018 Sep;21(9):1213-1220. doi: 10.4103/njcp.njcp_385_17. ↥
Angyal, Halasz, Meszaros, Kovacs, Kruk, Nemoda (2016): Potential salivary biomarkers and their genetic effects in a pilot study of adolescent boys with externalizing problems. Neuropsychopharmacol Hung. 2016 Dec;18(4):173-179. ↥ ↥ ↥