Dynamics of changes in skin lipids after stress: Effects of exogenous melatonin

Changes in the skin lipid composition induced by water-immersion stress in rats treated and untreated with melatonin were studied by thin-layer chromatography. Skin lipids showed a delayed reaction to stress. Melatonin exerted a protective effect which was manifested on the 2nd day after treatment in restoration of the level of total lipids and the absolute content of the majority of lipid fractions. The data suggest modification of, the metabolic relationships between skin lipids as well as lipids of the blood and subcutaneous adipose tissue. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 127, No. 5, pp. 519–522, May, 1999     

Skin lipids in rats administered with melatonin

Effects of the pineal hormone melatonin on skin lipids in Wistar rats were studied by thinlayer chromatography. The reaction was shown to be delayed. Contents of total lipids and the majority of fractions increased over 24 h after administration of melatonin. Concentrations of triglycerides and phospholipids decreased, while the contents of cholesterol, cholesterol esters, and free fatty acids increased by the end of the second day. Our findings indicate that the blood and subcutaneous fat, as well as changed metabolic interrelations of skin lipids are involved in the skin response to increased melatonin concentration. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 127, No. 4, pp. 463–465, April, 1999     

Effect of mesodiencephalic modulation on small intestinal mucosa after massive blood loss in rats

Effect of mesodiencephalic modulation on small intestinal mucosa was studied in rats subjected to massive blood loss. Massive blood loss induced structural changes in intestinal epitheliocytes typical of tissue hypoxia: intraintestinal edema, mitochondrial alterations, and microcirculation disturbances. A single session of mesodiencephalic stimulation carried out 60 min after massive blood loss produced a pronounced adaptive effect, restored disturbed structure of the intestinal villi, and induced compensatory hypertrophy of the mitochondria. This suggests that mesodiencephalic modulation promotes normalization of intracellular energy metabolism, improves the absorption capacity of bordered enterocytes, and restores the disturbed intestinal barrier. Translated fromByulleten’ Eksperimental’noi Biologii i Meditsiny, Vol. 130, No. 11, pp. 519–523, November, 2000     

Effect of partial transection of spinal cord on permeability of cutaneous vessels in rats before and after treatment with neurotoxic dose of capsaicin

Transection of the dorsal part of the spinal cord at the Th9 level disturbs permeability of blood vessels of thigh skin in rats. This effects is significantly inhibited by neurotoxic doses of capsaicin, which attests to the involvement of peptide-containing neurons. The data confirm the possibility of central modulation of the effector function of capsaicin-sensitive neurons. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 129, No. 4, pp. 402–403, April, 2000     

Effects of angiotensin II on DNA synthesis in the myocardium and epithelial tissues in newborn rats

The effects of angiotensin II on DNA synthesis in the myocardium and epithelial tissues of the skin and intestine were studied in 7-day-old albino rats by autoradiography. Angiotensin II significantly increase the labeling index of the nuclei and labeling intensity in myocardial cells and intensified cell proliferation in epithelial tissues. Thus, angiotensin II stimulates proliferative processes in the myocardium and epithelial tissues of the skin and intestine in newbown rats. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 126, No. 12, pp. 643–645. December, 1998     

Two mechanisms of progesterone action on the skin (Results of biochemical analysis)

Effects of progesterone on functional activity of lysosomes and lipid peroxidation are measured in the skin of rats in relation to its dose, duration of exposure to it, and skin tissue type (epidermis and dermis). This hormone is shown to regulate both lipid peroxidation intensity and lysosomal activity. It is concluded that these two affects represent two mechanisms through which progesterone exerts its anti-inflammatory effect on the skin. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 122, No. 8, pp. 173–176, August, 1996     

Effect ofRhodiola rosea on the resistance of isolated heart from stressed rats to ischemic and reperfusion damage

Experiments on isolated hearts from rats pretreated withRhodiola rosea and subjected to combined cooling and immobilization show that this adaptogen improves the resistance of the myocardium to ischemic and reperfusion damage and exerts a membrane-stabilizing effect. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 123, No. 5, pp. 514–517, May, 1997     

Effect of human apolipoprotein A-I gene on vasoactive properties of high density lipoproteins in rats of different age

Vasodilatory activity of high density lipoproteins and the content of apolipoprotein A-I in these particles decreases in senescent rats in comparison with adult animals. Implantation of human apolipoprotein A-I gene increases the content of this apolipoprotein in high density lipoproteins and improves their vasodilatory effect. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 125, No. 5, pp. 506–508, May, 1998     

Protective effect of adaptation to stress against the hemorrhagic shock-induced damage: the role of the antioxidant system

Modeling of hemorrhagic shock in rats adapted to immobilization stress required the removal of greater volumes of blood than that in control rats. The antioxidant system activation in adapted rats was accompanied by an increase in resistance to blood loss. The antishock effect of preliminary adaptation to stress was shown for the first time. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 126, No. 9, pp. 270–273, September, 1998     

Experimental study of the possibility of metabolic correction of maternal, fetal, and newborn hypoxia in rats using a new amino acid composition MR-33

The status of pregnant rats, their fetuses, and progeny exposed to oxygen insufficiency are compares. By the end of pregnancy the resistance to hypoxia markedly decreases. Newborn rats during nursing are highly resistant to hypoxia. When nursing period is over, the resistance to hypoxia drops, but later is gradually restored. MR-33 preparation produces a pronounced antihypoxic effect. Administration of the drug to pregnant rats not only appreciably improves their resistance to oxygen insufficiency, but also promotes adaptation and compensatory mechanisms in the progeny, thus helping the progeny to better tolerate hypoxia, particularly when its probability is particularly high. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 124, No. 10, pp. 451–454, October, 1997     

Postnatal stress impairs the learning of two-way avoidance task in prenatally alcoholized adult rats

Mild stress (handling and subcutaneous injection of 0.9% NaCl from postnatal day 8 through day 20) normally improves acquisition of a shuttle-box avoidance task in mature male rats. In the offspring of rats given intragastral injections of 25% ethanol (5 g/kg) from day 1 till day 20 of pregnancy, both handling and injections impair learning. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 123, No. 3, pp. 302–304, March, 1997     

Skin glycosaminoglycans in emotional stress

Here we studied the effects of water-immersion emotional stress on the components of several skin biopolymers in rats. The resistance of animals to stress was determined in preliminary experiments. This model of stress induced similar effects on the studied components in stress-resistant and stress-predisposed rats. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 127, No. 2, pp. 134–136, February, 1999     

Effect of the (3–4) fragment of substance P on brain ischemia in rats with different types of behavior

A single administration of a fragment of substance P 30 min after ligation of the common carotid arteries increases resistance to brain ischemia primarily in rats with a passive type of behavior (improves their neurological status and prevents posthypoxic hyperactivity), prevents posthypoxic hyperactivity in rats with an intermediate type of behavior, and lowers the resistance of rats with an active type of behavior (increases their mortality and aggravates their neurological status). Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 121, No. 4, pp. 399–403, April, 1996 Presented by P. V. Simonov, Member of the Russian Academy of Medical Sciences     

Effect of endothelin-1 on cardiovascular parameters of lewis and wistar rats in immobilization stress

Effect of low doses of endothelin-1 on the dynamics of blood pressure and heart rate is studied in Lewis and Wistar rats during 1-h immobilization stress. It is shown that endothelin-1 significantly lowers blood pressure in stress-sensitive Lewis rats during stress and has no effect on hemodynamic parameters in immobilized stress-resistant Wistar rats in comparison with the control. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 125, No. 3, pp. 275–278, March, 1998     

Protective effects of trimetazidine in acute hypoxia

Trimetazidine improves resistance to acute hypobaric hypoxia. Intraperitoneal injection of this preparation in an optimal protective dose (25 mg/kg) to rats prevents serious disturbances of energy metabolism and activation of lipid peroxidation in the brain, heart, and liver. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 125, No. 4, pp. 410–412, April, 1998     

Differential blood count and activity of lymphocytic dehydrogenases in rats with genetically different neuroendocrine status

Differential blood count and activity of lymphocytic dehydrogenases are studied in rats genetically liable to catalepsy and in Wistar rats. The activity of lymphocytic dehydrogenases is decreased, sex differences in activities of the studied enzymes leveled, and absolute counts of peripheral blood lymphocytes are decreased in rats liable to catalepsy. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 124, No. 5, pp. 555–557, May, 1998     

Dimebon improves learning in animals with experimental Alzheimer's disease

Systemic administration of antihistamine drug dimebon improves active avoidance conditioning in rats with chronic partial deprivation of cerebral cholinergic functions caused by intracerebroventricular injections of AF64A. The effects of dimebon on learning are similar to those of tacrine used in the treatment of Alzheimer's disease. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 129, No. 6, pp 640–642, June, 2000     

Effect of chorionic gonadotropin on irradiated animals

Chorionic gonadotropin exerts a protective effect on irradiated animals: it increases survival rate and number of peripheral blood leukocytes, improves the structure of liver parenchyma, and increases body weight. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 127, No. 5, pp. 536–538, May, 1999     

Magnesium deficiency in drinking water modulates blood pressure, Ca and Mg distribution in tissues, and compartmentalization of membrane-bound calcium in platelets of normotensive WKY rats

Magnesium deficiency in drinking water increases calcium-accumulating capacity of the aortic and myocardial walls in normotensive WKY rats, induces Ca resorption from bones, and impairs compartmentalization of membrane-bound Ca in platelets, resulting in accumulation of Ca in the external plasma membrane without changing blood pressure. Increased systolic blood pressure was characteristic of rats in Ca-deficient groups. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 127, No. 2, pp. 183–186, February, 1999     

Blood hyperviscosity syndrome: Adequacy of experimental model in SHR rats

In comparison with Wistar rats, SHR rats demonstrated significantly higher viscosity of the whole blood and plasma, fibrinogen content, and erythrocyte aggregation, but a lower erythrocyte deformability. The differences in hemorheological indices in SHR and Wistar rats correspond to the deviation of these indices in the blood hyperviscosity syndrome observed in hypertensive patients. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 126, No. 8, pp. 150–151, August, 1998