Effect of Skin Ion Channel TRPM8 Activation by Cold and Menthol on Thermoregulation and the Expression of Genes of Thermosensitive TRP Ion Channels in the Hypothalamus of Hypertensive Rats.

ISIAH (inherited stress-induced arterial hypertension) rats are characterized by high blood pressure and decreased gene expression in the anterior hypothalamus. Thermosensitive ion channel TRPM8 plays a critical role in the transduction of moderately cold stimuli that give rise to cool sensations. In normotensive animals, the activation of skin TRPM8 is known to induce changes in gene expression in the hypothalamus and induce alterations of thermoregulatory responses.

Thermoregulatory Response to Cold at Various Levels of Activation of Peripheral TRPA1 Ion Channel.

The effect of TRPA1-ion channel on thermoregulatory responses depending on the level of its activity was studied in Wistar rats. To activate the TRPA1 ion channel localized in the skin, its agonist allyl isothiocyanate (AITC) was used in different concentrations (0.04, 0.

Effects of activation of skin ion channels TRPM8, TRPV1, and TRPA1 on the immune response. Comparison with effects of cold and heat exposure.

The effects of pharmacological stimulation of skin ion channels TRPA1, TRPM8, TRPV1 on the immune response are presented. These effects are compared with the effects of different types of temperature exposures - skin cooling, deep cooling, and deep heating. This analysis allows us to clear the differences in the influence on the immune response of thermosensitive ion channels localized in the skin; (2) whether the changes in the immune response under temperature exposures are due to these thermosensitive ion channels.

Effect of Activation of Peripheral Ion Channel TRPM8 on Gene Expression of Thermosensitive TRP Ion Channels in the Hypothalamus. Comparison with the Effect of Cooling.

Experiments on rats showed that activation of the peripheral ion channel TRPM8 with menthol and rapid cooling (decrease in core temperature by 3°C) led to 1.5-fold activation of the expression of TRPV3 ion channel gene in the posterior hypothalamus, but had no effect on the expression of this gene in the anterior hypothalamus. Neither stimulation of peripheral TRPМ8, nor acute cooling affected the expression of genes for other thermosensitive ion channels (TRPV1, TRPV2, TRPV4, TRPA1, and TRPМ8) in the hypothalamus.

The influence of cooling and TRPM8 ion channel activation on the level of pro-inflammatory cytokines in normotensive and hypertensive rats.

The role of thermosensitive TRP ion channels in physiological processes in the whole organism is far from being clear. In present work we tried to understand the possible participation of the cold-sensitive ion channel TRPM8 in regulation of the pro-inflammatory cytokine level in blood, and to see if hypertension (widely spread disease) changes this relationship. Experiments were carried out on normotensive Wistar rats and rats with inherited stress-induced arterial hypertension.

5-HT2A receptors control body temperature in mice during LPS-induced inflammation via regulation of NO production.

G protein-coupled 5-HT2A receptors are involved in the regulation of numerous normal and pathological physiological functions. At the same time, its involvement in the regulation of body temperature (Tb) in normal conditions is obscure. Here we study the effect of the 5-HT2A receptor activation or blockade on Tb in sick animals.

Calcium ions facilitate body heat emission response to warming.

Involvement of various areas of the body surface in heat emission response to warming is characterized by a certain succession. The first response preceding the deep body temperature rise is dilation of ear skin vessels. Then, an increase in deep body temperature is counterbalanced by vascular reaction in the tail region, which plays the leading role in up-regulation of heat emission.

Effect of the sympathetic nervous system co-transmitters ATP and norepinephrine on thermoregulatory response to cooling.

The existence of co-transmitters of the sympathetic nervous system norepinephrine (NE) and ATP implies variations in the neuromodulator mechanisms of physiological processes. The role of ATP, as a transmitter of the peripheral part of sympathetic nervous system in the formation of thermoregulatory response is not clear. Whether ATP modulates any parameters of thermoregulatory response to cold; if yes, whether co-transmitters of sympathetic nervous system ATP and NE differently modulate thermoregulatory response and on which parameters of cold-defense response the influence of ATP is more pronounced.

Effects of pharmacological activation of TRPM8 ion channels on the thermoregulatory responses during warming.

Preliminary non-thermal activation of cold-sensitive TRPM8 ion channel facilitates initiation of the heat-defense responses in homoiothermal animals by decreasing temperature threshold of the vasodilatory response. TRPM8 activation leads to earlier heat-initiated increase in oxygen consumption, but reduces its magnitude. Warming inhibits the lipolytic effect of menthol activation of TRPM8 observed under thermoneutral conditions.

[Effect of transfer of fragment of chromosome 13, containing gene i16st on parameters of mouse temperature homeostasis].

Mechanisms of maintenance of temperature homeostasis in warm and under effect of cold were studied in mice of AKR strain and of its coherent strain AKR.CBA-D13Mit76 with the changed gene i16st encoding the gp 130 receptor, via which IL-6 performs its action. Under thermoneutral conditions and under action of cold, there were recorded temperature parameters, total oxygen consumption, carbon dioxide release, respiratory coefficient, and electrical muscle activity.

Central 5-HT3 receptor-induced hypothermia is associated with reduced metabolic rate and increased heat loss.

Activation of central 5-HT(3) receptors by the selective agonist m-CPBG (1-(3-chlorophenyl)biguanide hydrochloride, 40 nM i.c.v.

[Effect of TRPM8 ion channel activation on thermoregulatory response to cooling].

In rats, the effect of activation of the cold- and menthol-sensitive TRPM8 ion channel on different thermoregulatory parameters: total oxygen consumption, carbon dioxide release, respiration coefficient, constriction response of skin blood vessels, muscle activity, was studied. Activation of TRPM8 with menthol even in thermoneutral conditions produces an increase in oxygen consumption and a decrease in respiratory coefficient, which may suggest enhanced non-shivering thermogenesis and lipolysis. Rapid cooling against the background of TRPM8 activation is characterized by a decrease in the temperature thresholds of all thermoregulatory responses without associated changes in sequences of their initiation as well as in enhancement of metabolic component of emergency thermogenesis which leads to improved maintenance of core temperature in conditions when external cold acts on the organism.

Modulating effects of calcium on immune response of homoiothermal animal under thermoneutral conditions and during deep cooling.

Preliminary ionophoretic administration of Ca(2+) ions into the skin prevents the inhibitory effects of deep cooling on some processes characterizing the immune response. Differently directed changes in some immune response parameters induced by exogenous calcium and deep cooling suggest that competitive interactions between calcium-dependent processes can serve as mechanisms of functional changes in various physiological systems during the formation of the systemic reaction of a homoiothermal organism to cold.

Effect of rapid slight cooling of the skin in various phases of immunogenesis on the immune response.

Slight cooling had no effect on heat emission and heat production, but modulated the immune response to antigen in animals. Changes in the immune response upon rapid slight cooling of the skin (by 1.5 degrees C) depended on the phase of immunogenesis corresponding to cold exposure.

[Reconstitution of the function of the coupling complex of chloroplasts on phospholipid vesicles].

The function of H+-ATPase (CF1-CF0) complex from spinach chloroplasts was reconstituted on azolectin liposomes. Using these proteoliposomes, the 32P-ATP exchange reaction sensitive to dicyclohexylcarbodiimide and uncouplers was established. Combined incorporation of H+-ATPase and bacteriorhodopsin as a delta mu H+ inducer results in photophosphorylation.