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V A Konstantinov

Publications and source records attributed to V A Konstantinov.

15 recordsLinked to original sources
PubMed1990

[The frequency and sequence of the biopotentials of the cold thermoreceptors at different skin temperatures].

Electrical activity of the skin cold thermoreceptors was studied in the rabbit nasolabial area at a gradually decreasing temperature of the skin from 39.0 to 7.7 degrees C. The range of firing rate, the temperature of the maximal discharge, and the character of the discharge sequence at different skin temperature, were recorded for every thermoreceptor. The majority of the thermoreceptors were characterized by bursts of discharges (2-10 and more) at a certain skin temperature. The analysis of the data obtained revealed a wide variety of responses of the cold thermoreceptors to continuous drop of the skin temperature.

Animals↗
PubMed1980

[Effect of the temperature of different skin layers on the spike activity of cold thermoreceptors].

Changing of skin surface temperature by 18 degrees (from 22 degrees to 40 degrees) induced about 4.5 degrees temperature oscillations at 2--3 mm depth with 5--7 min delay. Simultaneous recording of activity of the rabbit upper lip cold thermoreceptors revealed that in 9 thermoreceptors alteration of activity occurred synchronously with skin surface temperature changes. In 7 thermoreceptors changes of activity were related to deep skin layer temperature. Localization of thermoreceptors in different skin layers seems to enable the organism to assess direction and intensity of the warmth flow spreading through the skin.

Action Potentials↗
PubMed1980

[Relation between the temperature of different skin layers and changes in the firing of cold cutaneous thermoreceptors].

On sharp changes (from 20 to 42 degrees C and vice versa) of temperature of the thermode placed on the upper lip of anesthetized rabbit, the temperature under the epidermis at the depth of 0.1--0.2 mm changed at the rate of 2 degrees/sec by 17.6 degrees .C on the average. At the depth of 2--3 mm the temperature only changed by 4.5 degrees C at the rate of 0.015 degrees/sec. Simultaneous recording of single cold thermoreceptors revealed two types of responses to alteration of the thermode temperature: with rapid increase in the firing rate during cooling and sharp decrease during warming up (18 thermoreceptors); and with slow, gradual change of the firing rate (10 receptors). The data obtained suggest that the cold thermoreceptors are situated in different skin layers. This enables the organism to register the skin temperature gradient as well as the transdermal warmth flows.

Action Potentials↗
PubMed1977

[Thermoregulation in rats in a helium-oxygen environment].

Effects of 21% O2 + 79% He mixture at the normal pressure on temperature of different body areas, blood temperature, heat emission, heat production, and the muscle electrical activity were studied at ambient temperature 21-22 degrees C. Action of the mixture during 60 min increased the heat emission by 21%, heat production by 17%, muscle activity by 37%. In spite of this, the temperature decreased in hypothalamus, cerebral cortex, rectum, muscles, and under the skin, as well as the blood temperature in the aortic arch and in the v. cava anterior. The occurring increase in the heat production is insufficient for preventing the drop of the body temperature. The disturbance of thermoregulation in the helium-oxygen atmosphere seems to occur mainly because of the excessive increase in the heat emission.

Animals↗
PubMed1975

[Mechanisms of development of thermoregulatory tone and cold shivering].

In rabbits, muscle potentials in response to factors increasing (low external temperature, inhalation of helium - oxygen mixture, electrical stimulation of the posterior hypothalamus) and decreasing the thermoregulatory muscle activity (high external temperature, inhalation of hypoxic mixture, electrical stimulation of the anterior preoptic hypothalamus), were studied. The thermoregulatory muscle tone and the cold chiver were shown to be independent forms of specific muscle activity with different regulating mechanisms. The increase or decrease of the muscles electrical activity occur because of a change of the muscle potentials amplitude rather than a change of the muscle oscillations frequency.

Animals↗