[Melatonin: ulcer disease and seasons of the year]. / Melatonin: iazvennaia bolezn' i sezony.

Melatonin produces a great variety of effects in human organism and plays an essential role in normal function of the body. This explains growing interest of medical researchers to this substance. The paper provides the results of 3-year studies of seasonal rhythm of melatonin production in patients with duodenal ulcer. Acute disorders of circadian and seasonal melatonin production in summer and autumn were discovered in patients with duodenal ulcer. These findings suggest involvement of abnormal melatonin production in pathological mechanisms of autumn exacerbations of duodenal ulcer.

[Melatonin production in hypertonic patients during magnetic storms]. / Produktsiia melatonina u bol'nykh gipertonicheskoi bolezn'iu vo vremia magnitnykh bur'.

AIM: To study mechanisms of action of natural magnetic field of the Earth on arterial pressure (AP) and melatonin production in patients with essential hypertension (EH) stage II. MATERIAL AND METHODS: Clinical, laboratory and device investigations covered 52 men with EH stage II (mean age 42 +/- 0.92 years) and 11 healthy men (mean age 23 +/- 1.46 years). Mean 24-hour, mean daytime, mean night systolic and diastolic pressures, 24-h index, time hypertensive index, standard deviation were registered. Melatonin was measured in the urine by radioimmunoassay. Geomagnetic situation was assessed by K-index (quiet--under 15, disturbed--15-25, magnetic storm--above 25). RESULTS: In hypertensive patients AP grew with growth of geomagnetic activity. In normal subjects AP remained normal. The 24-h rhythm of AP variability in hypertensives was normal. Magnetic storm affected melatonin production in EH patients noticeably: night and daytime production of melatonin was low. In normal subjects night melatonin production was high. CONCLUSION: AH stage II patients respond to magnetic storm with maladaptation, i.e. a rise in AP and low melatonin production.

[Melatonin production in patients with duodenal ulcer at different stages of disease]. / Produktsiia melatonina u bol'nykh iazvennoi bolezn'iu dvenadtsatiperstnoi kishiki v razlichnye stadii techeniia zabolevaniia.

Melatonin secretion was measured in patients with duodenal ulcer in exacerbation and remission. Melatonin production was found abnormal both in duodenal ulcer remission and exacerbation. It is suggested that melatonin may participate in pathogenesis of duodenal ulcer.

[Effects of disturbances of natural magnetic field of the Earth on melatonin production in patients with coronary heart disease]. / Vliianie kolebanií estestvennogo magnitnogo polia Zemli na produktsiiu melatonina u bol'nykh ishemicheskoí bolezn'iu serdtsa.

The obtained results clearly evidence for the influence of magnetic disturbances and storms on melatonin production in patients with ischemic heart disease. Improvement of 24-hour rhythm of melatonin secretion during the period of magnetic disturbances says in favour of this influence while an overall fall of melatonin production during magnetic disturbances and storms is an apparent negative factor.

[Emotional stress and blood melatonin levels]. / Emotsional'nyí stress i uroven' melatonina v krobi.

Blood serum melatonin concentrations were measured in male Wistar rats exposed to acute water-immersion emotional stress (ES) during intraperitoneal injections of physiological saline or different doses of melatonin. ES increased blood melatonin levels in rats receiving physiological saline 1 hour before or just after ES. When physiological saline was administered just ES, blood melatonin concentrations remained unchanged. The blood levels of melatonin both in control and stressed animals injected with exogenous melatonin were higher than those in rats given physiological saline alone. Immersion ES decreased blood melatonin concentrations in rats receiving different exogenous melatonin doses just before ES. However, in rats given melatonin, 1.0 mg/kg, after ES, its blood levels after ES was higher than those in the animals unexposed to stress. The findings suggest that it is just exogenous rather than endogenous melatonin that is consumed in rats injected with its different doses just prior to immersion ES.