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The gene expression of thermosensitive TRP (transient receptor potential) ion channels was studied by the method of quantitative reverse transcription-polymerase-chain-reaction (RT-PCR) in hypothalamus of control (normal) rats (5 weeks at the room temperature 20 +/- 22 degrees C) and rats adapted to cold (5 weeks at the room temperature 4 +/- 6 degrees C). For the first time in this brain region the expression of Trpv3 and Trpm8 genes was found, that was the evidence of the presence of TRPV3 and TRPM8 ion channels in the hypothalamus; it was made a comparison of the gene expression of the 6 thermosensitive ion channels (TRPV1, TRPV2, TRPV3, TRPV4, TRPA1, TRPM8) and found that there was rather high expression of the genes of thermosensitive ion channels activated at temperatures above 30 degrees C, while, the gene expression level of cold sensitive TRPM8 and TRPA1 proved to be much lower; it was found that long-term cold adaptation modified the gene expression of TRPV3 ion channel. The findings support the assumption that thermosensitive TRP ion channels of hypothalamus may be involved in the mechanisms of thermal adaptation at the level of gene expression.

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. Animals of the studied strains demonstrated different reactions to equal cold effect. At cooling, all mice of the AKR strain entered the state of hypothermia by decreasing metabolism. Mice of the AKR.CBA-D13Mit76 line showed 2 different types of reaction: 39 % of the animals of this strain reacted like mice of the AKR strain, but the majority (61 %) resisted actively to the cold action, which was manifested as a marked increase of metabolism. Taking into account the gene penetrance, this can indicate effect of the gene i16st on choice of the active ("regulated") or passive ("dependent") way of the organism reacting to temperature actions.

The mRNA expression of serotonin receptors 5-HT1A and 5-HT2A was investigated by the quantitative method RT-PCR in rats adapted to cold (5 weeks at +4 -(+6) degrees C) and in control (5 weeks at +20-22 degrees C). Four brain regions were examined: frontal cortex, hypothalamus, hippocampus, and midbrain. The influence of cold adaptation on the mRNA expression of 5-HT15 receptor was not found to be absent. The mRNA expression of 5-HT2A receptor changed under long-term cold exposure. These changes in different brain regions were various: in hypothalamus, there was an increase of the 5-HT2A receptor mRNA expression; in the cortex, a decrease; in the hippocampus and midbrain, significant changes of the mRNA expression were absent. The findings appear bo te adaptive and, according to their localization in the central nervous system, regulatory. They also suggest involvement of brain serotoninergic system in mechanism of adaptive reorganization of temperature regulation.

Laser doppler flowmetry was used for the intraoperative study of myocardial blood flow before and after revascularization in 116 patients with 2-3 vessel coronary artery disease and class II-IV angina. In patients without myocardial infarction, with microfocal myocardial infarction, or operated early after myocardial infarction revascularization caused no significant increase of myocardial blood flow. In patients with macrofocal infarction surgery was associated with significant increase of myocardial blood flow. Efficacy of revascularization could be assessed by lowering of flow gradients between various regions of the myocardium.

An assay of tryptophane hydroxylase activity in brain was based on fluorometric measurement of serotonin after condensation with o-phthalic aldehyde in 10 N HCl. The method proved to be more sensitive and simple as compared with the previously reported technique and enabled to measure the enzyme activity in brain samples as little as 10 mg. The method is recommended for laboratory routine use.