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Biomedical subjects

T V Kozyreva

Publications and source records attributed to T V Kozyreva.

At least 19 recordsLinked to original sources
PubMed2003

[Effect of cold on the antigen binding function of splenic cells at different periods of immunogenesis in rats].

The patterns of changes in the immune response when deep cooling with different rates acted at various periods during development of the immune response, were examined in Wistar rats. Cold exposure causes not only a suppression but also stimulation of the immune response to antigen. The suppressive effect of deep cooling when it preceded immune challenge (the antigen injected at a body temperature decreased by 3-4 degrees C) waned and became stimulating with increasing time interval between antigen challenge and cold exposure. The stimulating effect on the immune response was most pronounced when cold exposure occurred in 5 days after the antigen challenge. These changes differed quantitatively also when cooling was either rapid, or slow. Thus the modulating effect of the thermal afferent signal was differently manifested depending in the cooling rate, i.e. the presence or absence of the dynamic activity of the peripheral thermosensitive afferents, and the time elapsed between antigen challenge and cold exposure.

Animals↗
PubMed2002

Immune response and corticosteroid content in different regimens of cooling.

The effects of different cooling regimens modulating thermal afferent signal on the immune response were experimentally studied on rats. Immunization at low body temperature changed the immune response to the antigen. These changes depended on the depth and rate of previous cooling. The presence of dynamic activity of peripheral thermosensitive afferents potentiated the immune response after surface cooling and reduced the degree of suppression of the immune response after deep cooling. No clear-cut relationship between changes in the immune response and blood concentration of corticosterone during cooling was found.

Adrenal Cortex Hormones↗
PubMed1999

Effects of slow and rapid cooling on catecholamine concentration in arterial plasma and the skin.

Norepinephrine (NE) and epinephrine (Epi) concentrations in arterial plasma and in skin tissue were measured chromatographically before and after external cooling. Urethan-anesthetized rats were cooled either slowly (0.004-0.006 degrees C/s) or rapidly (0.03- 0.05 degrees C/s). Blood samples were drawn three times from each animal: 1) before cooling and at a rectal temperature decreased 2) by 0.5 degrees C and 3) by 3-4 degrees C. Skin samples were taken from controls and from rapidly or slowly cooled rats at a rectal temperature lowered by 0.5 degrees C. The resting mean values were 36.7 +/- 0.3 degrees C for rectal temperature, 0.62 +/- 0.079 and 1. 09 +/- 0.203 ng/ml for plasma NE and Epi, and 85.6 +/- 4.1 and 137.6 +/- 34.3 ng/g for skin NE and Epi. A decrease in rectal temperature by 0.5 degrees C at rapid cooling produced a 2.6-fold increase of NE and a 2.8-fold increase of Epi in plasma. Concomitantly, there was a significant decrease in skin NE concentration by 28% and Epi by 86%. At a rectal temperature decreased by 0.5 degrees C after slow cooling, plasma catecholamines did not change; at unaltered skin NE concentration, there was a reduction in skin Epi concentration (60%). When rectal temperature was lowered by 3-4 degrees C, the increase in plasma NE was virtually the same at both cooling rates and only plasma Epi increased more after deep rapid cooling than slow cooling. Thus the sympathoadrenal system may be differently activated depending on cooling rate. Rapid cooling, when the dynamic activity of the skin cold receptors is involved in the cold response, may provide conditions for an earlier activation of the sympathoadrenal system. This may evidence the functional significance of the dynamic activity of the skin cold receptors in the formation of the cold defense responses.

Animals↗
PubMed1998

[Modulating effect of peripheral thermoreceptors on human respiration].

Peripheral thermoreceptors substantially modulate respiratory parameters under normal and cooling conditions. Functional changes in peripheral thermoreceptors after cold adaptation promote alterations of the external respiratory system. Artificial modulation of the number of sensitive cold receptors by norepinephrine is shown by the pattern of a respiratory response to cooling. The pattern of respiration may be differently changed by affecting cold receptors of different sites. Thus, the possibility of initiating the same effector response does not mean that these sensors are equal in their responses. With a small number of effector organs in the body, the field of application of each effector is expanded due to the fact that they may be exposed to a variety of reception that differently modulating the function of an effector organ.

Adaptation, Physiological↗
PubMed1992

[The modulation of the functional properties of the skin thermoreceptors].

The characteristic property of skin cold receptors is the presence of static and dynamic activity with their maximum at any skin temperature. Parallel with the common properties there are some differences in the temperature range of receptors' functioning, frequency of static and dynamic activity, concentration of sensitive receptors on the skin. Mechanisms of these differences are unknown. It is found that the character of skin cold receptors functioning can be changed in individual life of the organism. Some parameters of static and dynamic activity as well as concentration of cold receptors functioning change both with adaptation of the organism to cold and with a rise of the noradrenaline concentration in blood. The reason of adaptive modifications of skin thermoreceptors may be an increase of their sensitivity to noradrenaline observed with adaptation to cold. It can be supposed that the modulating influence of biological active substances is very important in forming activity and sensitivity of skin thermoreceptors.

Adaptation, Physiological↗
PubMed1990

[Immunity status in persons participating in liquidation of the effects of the accident at the Chernobyl nuclear power plant].

The time course study of the immunity status of 57 subjects who were engaged in liquidation of consequences of the catastrophe at Chernobyl NPS in May-December, 1986, has revealed a high frequency of disorders in bactericidal and digestive activities of neutrophils, as well as in the functional activity of T-lymphocytes in the peripheral blood. The incidence rate of subjects with disturbed functional activity of T-lymphocytes is significantly higher in the group of subjects with suppressed capacity of blood lymphocytes for DNA repair as compared to those with normal levels of blood lymphocyte capacity for DNA repair.

Accidents↗
PubMed1990

[The static and dynamic activity of the cold receptors of the skin during noradrenaline infusion].

Experiments on rats have shown that cold skin receptors are sensitive to changes in the noradrenaline concentration. The initial rise of the noradrenaline concentration with infusion was accompanied by excitement of the most part of skin cold receptors. The establishment of a new higher level of noradrenaline concentration influenced both static and dynamic cold receptors activity. But this influence was different depending on the receptors frequency: excitement for low-frequency and inhibition for high-frequency receptors.

Animals↗
PubMed1990

[The results of the radiation treatment of cervical cancer using low, sensitizing doses of radiation].

Combined radiation treatment for cervical cancer is associated with radiation injury to the intestine, bladder, hemopoietic system and suppression of T-system, nonspecific immunity and thyroid function. Modified gamma-ray teletherapy was suggested which included low-dose (0.1 Gy) sensitizing irradiation of tumor and zones of regional dissemination prior to delivering therapeutic dose (1.9 Gy). The procedure assured lower incidence of radiation-induced reactions and complications, leukopenia and T-lymphocyte function suppression, stimulated nonspecific resistance and thyrotropic function of the pituitary, and provided normal function of the thyroid. As a result, five-year survival rate in patients with stage III cancer increased by 14%.

Adult↗
PubMed1989

[The functional value of the dynamic activity of cold receptors of the skin].

During abrupt cooling the dynamic activity of skin cold receptors is observed whereas it is practically absent during slow cooling. The influence of these two types of cooling on metabolic and skin blood vessels responses was studied in anesthetized rats. Acceleration of the cooling decreased the skin temperature threshold for metabolic response while the threshold for skin blood vessels constriction increased.

Animals↗
PubMed1985

[Mechanism of action of noradrenaline on cutaneous thermoreceptors].

The comparison of intradermal temperature, oxygen consumption and the rectal temperature with the skin cold-sensitive receptor responses to intraperitoneal and intraarterial noradrenaline injections shows that non-temperature changes following the increasing heat production or changing skin vessel tension are unrelated to augmentation of static receptors activity with rise of the noradrenaline concentration in the blood. It is possible that noradrenaline acts directly on thermoreceptors membrane. Apparently noradrenaline and sympathetic nervous system modulate the activity of the skin cold-sensitive receptors activity.

Adaptation, Physiological↗