Fiziolohichnyi zhurnal (Kiev, Ukraine : 1994)最新文献

In this research, we discover effect ofpolymorphism rs1801282 of the PPARG gene on the formation oxidative stress in patients with type 2 diabetes, depending on the duration of the disease: till 5 years, 5-10 years and more than 10 years. Activity of lipidperoxidation was assess in terms of diene conjugates (DC) and malonic dealdehid (MDA) and antioxidant system status - the activity of superoxide dismutase (SOD), catalase and the level of a-tocopherol (a-TF). Molecular genetic studies conducted by the method ofpolymerase chain reaction (PCR) in real time. During disease 5-10 years, found increase levels of DC and MDA in patients with polymorphism Pro₁₂--Ala for 34.9 and 34.7%, in compared with ProPro₁₂ --Pro (P=O. 01). Availability ProPro₁₂ --Pro stipulated reduction of catalase activity during disease 5-10 years at 75% (P=O. 001), andfor those, who are illfor more than 10 years at 2,04 times (P=O.01), which is not different from the reference level (F=1. 19; P=O. 600), but in the case ProPro₁₂ --Ala, this figure was in 2 times higher The main conclu- sion is that the type ProPro₁₂ --+Ala ofpolymorphism rs1801282 of the PPARG gene causes the development of oxidative stress in patients with type 2 diabetes with 5-10 years durations, and Pro Pro₁₂ --Pro - deficiency the enzyme catalase level of antioxidant system in patients with durations of disease more than 5 years.

Calcium influx though voltage-gated calcium channels mediate a huge amount of physiological events and cellular responses. Numerous scientific reports indicate that calcium channels are involved in synaptic transmission, neurotransmitter release, regulation of gene expression, cellular membrane voltage oscillations, pacemaker activity, secretion of specific substances from nerve and secretory cells, morphological differentiation, activation of calcium-dependent enzymes, etc. This review represents the modern classification, molecular structure, physiological and pharmacological properties of voltage-gated calcium channels expressed in mammalian cells.

In experiments in vivo we studied the effect of chronic iron-contained drug (Urfuhem) supplemention on the level of hemoglobin (Hb) in the blood of aging rats. To establish the biochemical mechanisms of drug action it were determined the parameters of oxidative/nitrosative stress and the hydrogei sulfide level in plasma and erythrocytes, the level of non-heme iron in plasma and erythrocytes sensitivity to acid hemolysis. It was found that in aging rats the drug significantly increases the Hb content of red blood cells and reduces its resistance to acid hemolysis. After the drug supplemention the rate of superoxide anion-radical (*0(2)(-)) generation in erythrocytes and stable hydrogen peroxide (H(2)0(2)) content both in plasma and erythrocytes, were down-regulated. The drug did not reduce the high levels of generation of the hydroxyl radical (*OH) and high levels of excess NO de novo synthesis by iNOS in erythrocytes but reduced the pools of nitrate anion(NO(3)(-))a its reutilization for NO synthesis. After thei drug supplemention the rate of constitutine NO synthesis by cNOS in aging rats plasma was up-regulated perhaps by cNOS coupling. The results indicate that the reason for increasing the permeability of the proton (H*) in red blood cells that causes the acid hemolysis in aging fats after the drug supplemention can be change in the balance of levels of oxidative and nitrosative stress in red blood cells in favor of the latter, and that toxic, OH generation is not at the expense of the classical Fenton reaction in the presence of iron ions (Fe(2+)); but due to the formation and decomposition of peroxynitrie (ON0O(-)).

This paper presents a comparison ofspectroscopic properties of aqueous humour in patients with cataract (60 patients, 60 eyes) and combination of cataract and primary open angle glaucoma (POAG, 36 patients, 36 eyes). The samples of aqueous humour were collected during the surgery. Both groups of patients were treated with different types of local drug antihypertensive therapy with different multiplicity and duration of instillation during the preoperative period. The absorption spectrum of aqueous humour were measured in the wavelength range 190-1100 nm. There were two absorption bands with maximums at 202 and 267 nm in the absorption spectrum (2nd maximum of some samples was shifted to larger wavelengths). The mean absorbance of aqueous humour at 202 nm in patients without POAG was significantly lower than in patients with POAG. This difference could be explained with accumulation of metabolites in aqueous humour of patients with POAG, which in turn may be caused by deceleration of aqueous humour flow in patients with POAG. Meanwhile, there were no statistically significant differences of mean absorbance of aqueous humour at 267 nm between the patients of both groups.

In experiments on white rats the character of effect of experimental hyperthyroidism was studied on the skeletal muscle (m. tibialis anterior) of white rats. It is shown that at experimental hyperthyroidism (rectal temperature of 38,5±0,10С) a muscle acquires high functional capabilities. It is shown that the latent period of generation and the time of development of positive wave “М-respones” are (-32%) and (- 22%). The latent period of shortening of muscle diminishes (- 23%) at single contraction. During experimental thyrotoxicosis (rectal temperature of 39,4±0,2 0 С) we observed physiopathological changes in the functional state of skeletal muscle: the lengthening of the latent period of generation of “М-respones” (+21%), an increase in the time of development of positive wave (+54%) and of latent period of shortening of muscle (+14%). It is concluded that in experimental hyperthyroidism and thyrotoxicosis the functional state of skeletal muscle changed in different directions.

Glycolysis and glutaminolysis as well as endoplasmic reticulum stress are required for tumor progression suggests through regulation of the cell cycle. Inhibition of ERN1/IRE1 (endoplasmic reticulum to nucleus signaling 1/inositol requiring enzyme 1), a central mediator of endoplasmic reticulum stress, significantly suppresses glioma cell proliferation and tumor growth as well as modifies sensitivity gene expressions to glucose and glutamine deprivation. We have studied the expression of genes encoded transcription factors such as E2F8 (E2F transcription factor 8), EPAS1 (endothelial PAS domain protein 1), HOXC6 (homeobox C6), TBX3 (T-box 3), TBX2 (T-box 2), GTF2F2 (general transcription factor IIF), GTF2B (general transcription factor IIB), MAZ (MYC-associated zinc finger protein, purine-binding transcription factor), SNAI2 (snail family zinc finger 2), TCF3 (transcription factor 3), and TCF8/ZEB1 (zinc finger E-box binding homeobox 1)in U87 glioma cells upon glucose and glutamine deprivation in relation to inhibition of IRE1.We demonstrated that glutamine deprivation leads to up-regulation of the expression of EPAS1, TBX3, GTF2B, and MAZ genes and down-regulation of E2F8, GTF2F2, TCF8, and TBX2 genes in control glioma cells.At the same time, glucose deprivation enhances the expression of EPAS1 and GTF2B genes and decreases of E2F8, HOXC6, TCF3, and TBX2 genes in these glioma cells. Inhibition of IRE1 by dnIRE1 significantly modifies the expression most of studied genes with different magnitude. Present study demonstrates that fine-tuning of the expression of proliferation related transcription factor genes depends upon glucose and glutamine deprivation in IRE1-dependent manner and possibly contributes to slower tumor growth after inhibition of IRE1.

The dynamics of the balance of indices of pro- and p53- Bcl-2 anti-apoptotic processes in the hippocampus of rats with experimental diabetes mellitus (DM) complicated by incomplete global cerebral ischemia-reperfusion was investigated. It is shown that p53 proapoptotic processes in animals without diabetes after 20 minutes of ischemia/l hour reperfusion in all fields of the hippocampus are activated in the background of increasing Bcl-2 antiapoptotic processes in the fields CAl, CA2, CA4 and depression of it - in the CA3 field. In the early postischemic period in rats with DM activity of the p53-proapoptotic processes in fields CAl, CA3, CA4 significantly exceeds that in non-diabetic rats (area of p53- IRM increases on 110, 60 and 27 %), and was significantly lower than that detected in CA2 field. On the 12th day of post-ischemic period, activation of apoptosis in field CAl occurs in the background of inert antiapoptotic processes, in animals without diabetes, as well as in diabetic rats, but the indicators characterizing of apoptotic activity in rats with diabetes were higher (specific contents of p53 protein and area ofp53 -IRM increases on 38 and 43 %). During this period, in the CA2 region of the non-diabetic animals, some depression of the antiapoptotic processes with a slight predominance of proapoptotic processes was detected. In the field of CA3 region of rats without diabetes, the retention of activity of proapoptotic processes and the deepening in the dynamics of depression of antiapoptotic processes were showed. In rats with DM, the oppression of both mechanisms with a significant depression of antiapoptotic processes was observed. On the 12th day of experiment in the field CA4, the most balanced relationship were detected between the studied of the processes due to their parallel and unidirectional changes both in the rats without diabetes as well as with DM. The results point on the modifying effect ofDM on susceptibility ofhippocampal fields to ischemic-reperfusion injury.

We investigated the role of changes in the endogenous nitric oxide (NO) metabolism during the influence of succinic acid amides as biotransformation products of an anti-diabetic drug on the state of hemostasis. In experiment with rats, synthetic succinamides were applied in quanti- ties equimolar to the sub-toxic dose of the pharmaceutical substance. We investigated the indicators characterizing the state of platelet and coagulation hemostasis in the blood plasma, the content of the stable NO metabolites and the activity of nitrogen oxide synthase (NOS) in the liver homogenate, blood plasma and urine of rats. We found that sub-chronic succinamides introduction reduced the nitrite and nitrate anions concentration in the blood plasma (by 30-50 and 20-35% resp.), liver (by 16-19 and 14-18%) and urine (by 50-70 and 38-55%). These changes were essentially dependent on the reduction in the NOS activity (by 33%). The studied compounds showed a 1.5 fold increase in the coagulation potential of the blood plasma and cause a 20% boost in the aggregation of thrombocytes. Analysis of the pair correlation coefficients showed positive association of the changes in indicators of the NO metabolism and hemostasis. The obtained results suggest that the registered manifestation of the pro-coagulation and thrombogenic action of succinamides applied in the sub-toxic doses is partially determined by a drop of the vasoactive NO pool that in turn, occurs due to a decline of the NOS activity.

The changes in arginase activity of spermatozoa and hormonal profile of peripheral blood of infertile men with various forms pathospermia have been studied. It has been found that arginase activity in the sperm cells of men with oligozoo-, antenozoo-, oligoastenozoo- and leucocytospermia is decreased in 2.1, 2.3, 2.4 and 3.3 times respectively. This indicates about inhibition of arginase pathway of L-arginine metabolism, which is not significantly dependent on the type of disruption of spermatogenesis. The most significant changes have been observed in infertile men with leucocytospermia since white blood cells stimulate the formation of reactive oxygen species, induction and development of oxidative and nitrative stress in spermatozoa. Inhibition of arginase pathway of L-arginine metabolism has adaptive role, which is to limit bioavailabil- ity of L-arginine and to prevent excessive formation of NO in cytotoxic concentrations to sperm cells. It has been noted changes in serum concentrations of gonadotropin and sex hormones in men with various forms of pathospermia. The most expressed significant changes were in levels of follicle stimulating hormone and testosterone. The concentration of follicle stimulating hormone in patients with oligozoospermia caused by hypogonadism is twice higher and in patients with leucocytospermia in 1.8 times higher than in fertile men. In patients with astenozoospermia this value is in 2.2 times lower than in normozoospermic samples but within the physiological norm. The testosterone level in men with oligozoospermia is in 1.6 times lower than in fertile men but within the physiological norm. It has been found that arginase inhibition of spermatozoa po6itively correlated with a decrease in their concentration in the ejaculate of infertile men with oligozoospermia (r =0.68).

Changes in amplitudes of evoked inhibitory postsynaptic currents (eIPSCs) from rat cultured hippocampal neurons were studied using whole-cell patch-clamp technique in postsynaptic neuron and local extracellular electrical paired pulse stimulation of single presynaptic axon. Paired pulse depression (PPD) and paired pulse facilitation (PPF) were observed in studied 43 neurons. According to coefficient of variance (CV) analysis was found that CV of second respond was significantly larger than CV first by 57 % (n 26) during depression and significanty smaller by 27 % (n = 17) during facilitation. Thus, only presynaptic mechanism underlies short-term depression and facilitation. We also estimated quantal parameters assuming that transmitter release is reasonably described by a binomial distribution. We found that under our experimental conditions there were no significant changes in GABA release probability during PPD and PPF. The values of mean quantal content and mean number of sites of transmitter release were the same for first stimulus in pair and were equal 9.7 in depression and 5 in facilitation of synaptic transmission. The values both of them for second stimulus were significant decreased by 28 and 26% during PPD and were significant increased by 14 and 11% during PPF, respectively. Thus, there is significant difference in quantal parameters characterizing GABA release during short-term depression and facilitation of synaptic transmission.