Metabolic stress response patterns in urinary compositions of idiopathic calcium oxalate stone formers, patients with chronic bowel diseases and controls.

Emotional stress is associated with e.g. increased hormone release, high blood-sugar level and blood pressure. Stress clearly affects metabolism. Whether chronic stress exposure leads to altered urinary compositions with increased risk of CaOx; urolithiasis was examined by investigating the relation between stress burden and urine composition. 29 controls (CG), 29 CaOx stone formers (SF), and 28 patients with chronic inflammatory bowel diseases (CIBD) were advised to avoid unfavorable aliment. Any urolithiasis-related medications were stopped. At day 5, a 24-h urine was collected and comprehensive urinalysis performed. AP (CaOx) index was calculated. Subjects completed a questionnaire designed to measure perceived stress ("Trier-Inventory-of-Chronic-Stress"). Mean AP (CaOx) in CG, SF and CIBD amount to 0.8 (+/-0.3), 1.2 (+/-0.7), and 1.9 (+/-1.2), respectively. Increased AP (CaOx) in SF is mainly attributed to an increased effect of calcium and oxalate, whereas in CIBD this is additionally caused by a reduced effect of citrate, magnesium and volume. Stress dimensions are correlated to any investigated urinary parameter with an absolute value of r < or = 0.600; some correlations are statistically significant: whereas in SF only one combination, "lack of social recognition" versus calcium, shows significance, in CIBD various combinations are significantly related. In particular, sodium excretion increases with stress. In CG, some stress dimensions are directly related to citrate; with increasing stress, protection against CaOx crystallization tends to increase. It could be shown that stress load and urinary composition are related by statistical means. The observed metabolic stress response patterns in urinary compositions are different for the distinct groups, thereby, reflecting a conclusive picture. This is in particular in CIBD, for which a link between stress and inflammatory activity and between inflammatory activity and altered urinary composition is well established.

Correlations between the autonomic modulation of heart rate, blood pressure and the pupillary light reflex in healthy subjects.

Information on autonomic modulation can be derived from different organs that are innervated by the sympathetic and the parasympathetic nervous system, when assessing e.g. heart rate or blood pressure fluctuations or the pupil's reaction to light. Correlations between parameters from different target organs might reveal information on hierarchically higher centres of autonomic integration. Here, we obtained parameters of heart rate variability, blood pressure variability, baroreflex function and light reaction pupillography from 50 individuals and tested the hypothesis that these are associated. Pupil diameter and constriction latency significantly correlated with parameters of heart rate variability, but not with those of blood pressure variability. In contrast, relative amplitude significantly correlated with blood pressure variability only. In conclusion, the different branches of the autonomic nervous system examined here are not associated unequivocally but show a distinct pattern of interrelations in healthy subjects. Examinations as described here might add to the diagnosis of autonomic dysfunction and reveal differential patterns in certain disease states.