[Expression of epidermal growth factor receptor and plasmatic level of melatonin in simple and complex endometrial hyperplasia].

The goal of our research was to find the prognostic significance of the epidermal growth factor receptor (EGFR) in the hyperplastic endometrium. Immunohistochemical study of morphological material (endometrial scrap) was conducted in order to reveal the EGFR expression (in 35 patients). The study of consistence of melatonin (universal antiproliferative and anticancerogenic hormone) in patients' blood serum was performed as well (using ELISA method). The numeric data of investigation were processed statistically using the SPSS-12 program and IBM SPSS Statistics, 20. According to received results, the more complicated the type of endometrial hyperplasia is, the stronger EGFR expression is and the more melatonin consistence is reduced in blood plasma. However, sometimes much lower level of melatonin not only in case of complex hyperplasia (with atypia), but also in case of simple hyperplasia (without atypia) was observed. In addition, melatonin consistence is in norm not only in case of simple hyperplasia, but also in case of complex hyperplasia. Also, unimportant reduction of melatonin level is seen in plasma in case of both types of endometrial hyperplasia (without atypia): if, for example, in simple hyperplasia, this slight reduction of melatonin level in plasma is seen in condition of sharp EGFR expression, the same amount reduction of plasmatic melatonin in complex hyperplasia is seen in condition of weak EGFR expression. To sum up: in case of simple endometrial hyperplasia without atypia, reduction of plasma melatonin level should be a bad prognostic indicator and this condition can be followed by transformation of hyperplasia into atypical form; the normal plasmatic level of melatonin in complex endometrial hyperplasia without atypia (in condition of weak EGFR expression) should be a good prognostic indicator; unimportant reduction of plasma melatonin level and in addition, EGFR sharp expression in simple hyperplasia, is probably the sign, that hyperplasia can change and become complex; however, the same indicators of plasma melatonin level (on the background of weak EGFR expression) in complex hyperplasia (without atypia) should not indicate the poor prognosis.

Pancreatic D-cells in aging and intraislet effects of pancreatic somatostatin.

In old organisms pancreatic D-cells are not changed in number. During the aging in mentioned cells takes place the intensification of secretory and extrusive functions, which are more prominent in old organisms than in young ones. Peripherally situated D-cells are vascularly ineffective within the pancreatic islet and do not suppress locally B- and A-cells. D-cells' major target tissue may be pancreatic acinar cells. Functionally activated D-cells in old organisms may play the main role in the development of involutive processes in exocrine pancreas and in its atrophy. Stagnation of the secretory granules in pancreatic A- and B-cells in old ages could not be caused by influence of paracrine effect of somatostatin. The given process could be considered as a result of reduction of energopotentials and suppression of signal ways for initiation of insulin and glucagon secretion. Respectively, extrusion impediment of secretory granules resulted in their stagnation could be explained by suppression of exocytosis as an energy- and signal-dependent process. We suppose that cytotopographic and microvascular peculiarities of pancreatic islets in human beings and rodents is a reflection of intensification of insulin apparatus and is directed to loose the B-cells from the local (microvascular or paracrine) influences (effects of D- or A-cells). The mentioned is of high physiological importance (especially in the process of aging) for the organisms of above-presented taxonomic groups due to rich amount of carbohydrates in their food ration. The above-mentioned fact gains the special importance in human beings, where evolutionary "solitary" (represented by single B-cells) insulin apparatus is faced with evolutionary "rooted" strong and diverse contrainsulin apparatus, leading to development of diabetes mellitus (type 2) in late ages.

[Biochemical and clinical aspects of melatonin biosynthesis induced by noradrenalin in experiment].

Melatonin has been considered as a hormone with potent immunomodulating, anxiolitic and antioxidative properties. Melatonin is also known to be inhibitor of sympatoadrenal activity. The study was aimed to elucidate changes in melatonin synthesis induced by noradrenalin IM injection. Melatonin plasma levels were detected by radioimmunoassay. All studies were performed conducted on white non-linear rats. By the 20th day after noradrenalin administration plasma level of melatonin was significantly decreased. In conclusion, short-term activation of sympatoadrenal system (i.e. stress-induced activation) is accompanied by elevated plasma levels of melatonin, however long-term hyperactivity of the sympatoadrenal system atrophy of epiphiseal parenchyma develops followed by decreased melatonin synthesis. It has been considered that melatonin might contribute to chronic stress-induced process associated with involution of thymus and lymphatic nodes, hypertrophy of adrenal cortex. Data obtained might be taken into consideration during the treatment of stress-induced conditions.

[Biochemical, pharmacological and clinical aspects of influencing methioninc, tryptophan, pyridoxine (vitamin B6), Ca2+ and high-calorie food on the synthesis and intensity of the secretion of melatonin].

The goal of the investigation was the determination of the influence of Ca(2+), vitamin B6 methionine, tryptophan, the combination of the listed elements and high-calorie food on the intensity of synthesis and secretion of melatonin. The level of melatonin in the blood serum was being determined through the method of radio-immune (immune-enzyme) analysis. Based on the results received it was found out that the influence of the vitamin B6, tryptophan and their combination in the organism of the tested objects - white rats) resulted in the considerable increase of formation of melatonin. In the conditions of feeding them with high-calorie food - the value of melatonin in blood is sharply reducing. Consequently we may conclude that the vitamin B6 and tryptophan separately and in combination, either directly or through some other mechanism participate actively in biosynthesis and secretion of melatonin. The high-calorie food through unknown mechanism to us reduces the formation of the melatonin in epiphysis. This might point to the important role of the deficit of melatonin in etiopathogenesis of the diseases, detected and developed on the background of hypercholesterinemy.