Differences in the Sensitivity of the Baroreflex of Heart Rate Regulation to Local Geomagnetic Field Variations in Normotensive and Hypertensive Humans.

Synchronization between heart rate variability (HRV) in the low-frequency (LF) range (0.04-0.15 Hz) and 1-min variations in the components (X, Y, Z)and the total vector (F) of geomagnetic induction (nT) was studied in normotensive (blood pressure up to 140/90 mmHg) and hypertensive (blood pressure above 140/90 mmHg) individuals living in the Arkhangelsk region (60°51'52″ N 39°31'05″ E).

Phase Analysis of Ultradian Rhythms of Body Temperature in Laboratory Mice Maintained under Constant Illumination at Different Longitudinal Locations.

The study examined the rhythmic oscillations of body temperature with the period ranging 100-400 min in three groups of laboratory mice maintained under persistent artificial illumination in Moscow and Ulyanovsk. The difference in the moments of sunrise or sunset in these towns is about 1 h. The greatest rhythmic oscillations of body temperature in examined mice had the periods of 100-400 min.

[Annual blood pressure dynamics and weather sensitivity in women].

Aim: To study the annual cycle of blood pressure (BP) and weather sensitivity in normotensive women aged 20-59 years.

Subjects And Methods: The same group of 25 non-smoking women who had been living in the European North of Russia (62° N, 51° E) almost since their birth and were engaged in moderate-intensity mental labor was daily examined. During a year, there were 11823 blood pressure measurements using the Korotkoff technique; heart rate was calculated by palpation.

Magnetic storms and variations in hormone levels among residents of North Polar area--Svalbard.

In the present work four examinations (January, March, June, October 1991-1992) of the blood concentration of adrenal hormones (cortisol) and thyroid hormones (triiodothyronine (T3) and thyroxine T4) and their dependence on space and terrestrial weather parameters have been done for large groups of healthy inhabitants of high latitudes (Svalbard, the most northerly in the world year-round inhabited settlements). The aim of this study was to find the possible sensitivity of these biochemical parameters to variations of external natural factors at high latitudes in three independent groups of people living in this region (miners and people working underground (364 samples), the men working on the ground (274 samples) and women working on the ground (280 samples)). The obtained data indicate that the most expressed dependence of concentration of the three studied hormones is on the level of geomagnetic activity (GMA) - Kp, Ap, Kpmax - 3h.

[The dynamics of pulse rate and biochemical parameters in blood of healthy individuals in relation to Pc5-6 geomagnetic pulsations].

Four experiments on long-term monitoring of pulse rate and blood biochemical parameters in four healthy volunteers (women) were conducted. The duration of each experiment was 90 minutes, electrocardiography was performed continuously, taking blood sampling every two minutes. In venous blood the current concentrations of triiodothyronine, cortisol, glucose, stable metabolites of nitrogen oxides (NO(x)) were determined.