Pine nodule extract and its component, SJ-2, have been reported to have an inhibitory effect on catecholamine secretion induced by acetylcholine (its physiological secretagogue) in cultured bovine adrenal medullary cells (J Pharmacol Sci., 2017).
　The present study aimed to determine the effect of pine nodule extract on the autonomic nervous activity induced by mental stress (Uchida-Kraepelin arithmetic test) in healthy young students. Autonomic nervous balance was measured by power spectral analysis of heart rate variability using a standard hexagonal radar chart. Four 15-min repetitions of an arithmetic task served as an acute mental stressor that caused an increase in sympathetic parameters in the placebo group, while no increases in sympathetic parameters were observed in the pine nodule extract group.
　The present study demonstrated that the assay system of the autonomic nervous balance detected increases in sympathetic nervous activity induced by acute arithmetic stress in the placebo group, but that those increases were cancelled in healthy young students who ingested pine nodule extract, suggesting that this pine nodule extract may an anti-stress effect.