Metabolic features of the adaptive effect of delta-sleep inducing peptide and piracetam under hyperoxic conditions.

Adaptive effects of delta-sleep inducing peptide (DSIP, 12 microgram/100 g body weight, single intraperitoneal injection) and piracetam (3 mg/100 g body weight, daily intraperitoneal injection for 3 days) are manifested via differential changes in neurotransmitter amino acids (GABA, glutamate, aspartate), modulation of transport ATPase activity, and decreased accumulation of lipid peroxidation products (conjugated dienes, malonic dialdehyde, Schiff bases) in various fractions of neuronal membranes (myelin, synaptic and mitochondrial membranes) in the sensomotor cortex of rat brain. Under hyperbaric oxygenation (0.3 MPa for 2 h), the combination of DSIP and piracetam enhanced the protective effect of each compound.     

Effect of delta sleep-inducing peptide on lipid peroxidation and xanthine oxidase activity in rat tissues during cold stress

I. p. administration of exogenous delta-sleep-inducing peptide (DSIP) decreased the amount of diene conjugates and Schiff bases in the liver and brain in rats. The xanthine oxidase activity, at that, did not change. Cold stress enhanced the xanthine oxidase activity well as the amount of diene conjugates and Schiff bases. Preliminary administration of the delta-sleep-inducing peptide to cold-exposed animals diminished the xanthine oxidase activity and lipid peroxidation in the liver and brain. Protective effects of the DSIP under stress is discussed.     

The effect of abscisic acid on cold tolerance and chloroplasts ultrastructure in wheat under optimal and cold stress conditions

The effect of abscisic acid (0.1 mM) on cold tolerance of leaf cells and ultrastructure of chloroplasts in wheat (Triticum aestivum L.) under optimal (22 °C) and cold stress conditions (4 °C) was studied. Results indicated that exogenous abscisic acid induces a rise in the cold tolerance of wheat along with a number of significant ultrastructural changes in chloroplasts both at 22 and at 4 °C. Some of them (increase in density of chloroplasts stroma, formation of “distorted” and “dilated” thylakoids, appearance of invaginations, changes in the shape of chloroplasts and increase of their dimension owing to the stroma area) were common to the two types of treatments. At the same time, the character of changes in the membrane system of plastids was temperature specific, i.e. if at 22 °C the hormone caused a considerable increase in the length of photosynthetic membranes in chloroplast owing the length of both appressed and non-appressed membranes of thylakoids, then in cold stress conditions observed an increase in the number of grana and the length of appressed membranes of thylakoids. These results suggested that the rise in the cold tolerance of abscisic acid-treated plants is associated with the ultrastructural reorganization of chloroplasts aimed to defense plant cells against chilling injury and to maintain the activity of the photosynthetic system.     

Regulatory effect of delta sleep-inducing peptide on the activity of antioxidant enzymes in erythrocytes and tissues of rats during cold stress]

Antioxidant system's state of erythrocytes and tissues in rats under normal and cold stress conditions was studied. Intraperitoneal injection of exogenic DSIP at the dose of 12 mkg/100 g body weight both, to intact and to cold-exposed animals results in the increase of superoxide dismutase, catalase, glutathione peroxidase, glutathione reductase activities and concentration of glutathione in red blood cells, liver and brain.     

The effect of adaptation to cold and re-adaptation to room temperature on the level of glutathione in rat tissues

1. Glutathione (GSH) was assayed in plasma, liver and IBAT in control (22±1°C) and cold adapted rats (45 days in 5±1°C), and in rats cold adapted and brought back to room temperature after 1, 3, 7 and 15 days.

2. Adaptation to the cold led to reduced GSH in the liver and plasma while the level in intrascapular brown adipose tissue (IBAT) was increased in comparison to controls.

3. On the first day of re-adaptation, plasma GSH was similar to the control level, as were hepatic levels on the first and fifteenth day, but GSH in IBAT remained higher even after fifteen days.

Histochemical studies on phosphorylase activity in the tissues of the albino rat under normal and experimental conditions

Summary Various substrate mixtures have been tested for the histochemical demonstration of phosphorylase in tissue blocks. These studies indicate that phosphorylase activity, cytological detail and localization of the reaction product are optimally demonstrated when tissue blocks are incubated for one hour or longer in a medium containing high concentrations of G-1-P, ATP and PVP.Abbreviations AMP adenosine-5-monophosphate - ATP adenosine-5-triphosphate - EDTA ethylenediamine-tetraacetic acid - G-1-P glucose-1-phosphate - PPa active phosphorylase - PPb inactive phosphorylase - PVP polyvinyl pyrrolidone     

The effect of naloxone and delta-sleep inducing peptide on the homocarnosine content of brain tissue

The intraventricular and intravenous administration of naloxone was studied for its effect on the homocarnosine amount in cerebral hemispheres, striatum, hippocamp, hypothalamus, thalamus, cerebellum, medulla oblongata as well as in the spinal cord of rabbits. The intracysternal administration of naloxone decreases the homocarnosine amount in the striatum, hypothalamus, cerebellum and medulla oblongata. The intravenous administration of peptide exerts no statistically reliable effect on the homocarnosine content in the rabbit brain. The intraperitoneal administration of delta-sleep-inducing peptide increases sharply the homocarnosine content in the rat brain.     

Effect of delta-sleep peptide on the ultrastructural features of the rat sensomotor cortex

The performed studies have shown that injection of DSIP causes an activation of nuclear apparatus and plastic metabolism in III-Y layer of the rat cerebral cortex. The activation of axo-axon and axosomatic synapses indicates the modulation of inhibitory processes in the cerebral cortex.     

Plasma thyroxine and cortisol under basal conditions and during cold stress in the aging dog

The effects of aging on plasma concentration of thyroxine (T4) and cortisol and on responses of these hormones to low ambient temperatures were determined in the dog. Female beagle dogs were divided into three age groups: old, adult, and puppies. The mean (+/- SD) ages were 11.4 +/- 0.2 years, 3.0 +/- 0.4 years, and 7.6 +/- 0.2 weeks, respectively. All dogs came from a genetically homogeneous colony and were free from any disease. The adult and old dogs were used during anestrus. Based on four daily blood samples, the mean (+/- SE) T4 level in the old dogs (2.8 +/- 0.1 microgram/dl) was significantly (P less than 0.001) lower than that in the adults (4.2 +/- 0.2 micrograms/dl) and puppies (4.4 +/- 0.2 micrograms/dl). By contrast, mean plasma cortisol levels in the old dogs (21.1 +/- 3.1 ng/ml) and adults (15.4 +/- 2.4 ng/ml) were significantly higher than those in the puppies (7.2 +/- 1.1 ng/ml). No significant changes in plasma T4 and cortisol occurred in any of the three age groups at 22 degrees C or during exposure to 10 or 4 degrees C. Exposure to -5 degrees C, however, produced significant increases in T4 (greater than 130% by 5 hr) and cortisol (greater than 280% by 1 hr) in adult dogs. This temperature produced only a modest increase in T4 (70% by 3.5 hr) and no change in cortisol in the old dogs. The puppies showed no change in T4 and cortisol during exposure to -5 degrees C. The results demonstrate that with advancing age, plasma T4 and cortisol concentrations change in opposite directions, thus supporting the hypothesis of a negative relationship between these two hormones. These results also show that the responses of these hormones to the stress of cold decline during aging and are not yet developed in the very young.     

Effects of beta endorphin and delta-sleep inducing peptide on resistance to emotional stress

Enzyme immunoassay was used to study the contents of beta-endorphin and delta-sleep inducing peptide (DSIP) in blood and hypothalamus in rats of Wistar and August lines under acute emotional stress. The stress-resistance of the animals was determined by using preliminary behavior tests. The rats were divided into two groups and predisposed to acute emotional stress. It was found that the contents of these peptides in Wistar-rats, which are more resistant to emotional stress, were higher compared with the August-rats, which are more predisposed to emotional stress. It was shown that the contents of beta-endorphin and DSIP in Wistar-rats is higher than in predisposed Wistar-rats.     

人参多糖对低温应激大鼠颗粒细胞与卵母细胞的调节

目的 应用体外细胞培养观察人参多糖对低温应激大鼠卵巢卵母细胞发育与颗粒细胞蛋白合成的影响,为研究人参多糖对低温应激大鼠卵巢功能的变化,提高机体耐寒能力提供科学实验解释.方法 培养Wistar大鼠卵巢卵母细胞与颗粒细胞,设37℃对照组,0、-15、-25与-35℃低温应激实验组,观察细胞计数.采用放免分析法测定3H-TdR与3H-Leu CPM值.结果 带卵泡卵母细胞低温应激实验组与对照组比较,生发泡破裂百分率57.14%/36.70%,人参多糖组68.97%/41.13%;带卵丘卵母细胞低温应激实验组与对照组比较,生发泡破裂百分率75.71%/41.14%,人参多糖组71.21%/39.28%,P＜0.05.3H-TdR掺入量人参多糖为参照与对照组比较,人参多糖实验组为1279±191与913±212,低温人参多糖实验组均值为651±211与499±116.低温应激为参照与对照组比较低温实验组均值为499±116与913±212,低温人参多糖实验组均值为651±211与1279±191,P＜0.05.3H-Leu掺入量人参多糖为参照与对照组比较,人参多糖实验组为889±153与617±119,低温人参多糖实验组均值为431±1144与300±119.低温应激为参照与对照组比较低温实验组均值为300±119与617±119,低温人参多糖实验组均值为431±144与889±153,P＜0.05.结论 低温应激抑制卵母细胞发育与颗粒细胞蛋白合成,人参多糖能促进卵母细胞成熟,能使低温应激大鼠卵巢颗粒细胞蛋白合成增加,而对带卵丘的卵母细胞无作用.     

Kinetic properties of rat heart cathepsin D under normal conditions, during emotional-pain stress and in the post-stress period]

Cathepsin D preparations have been isolated from the heart of healthy animals and stress-surviving rats by the method of affine chromatography with the hemoglobin-biogel-P300 sorbent. To analysis of the obtained data permits concluding that acute stress stimulates activation of the catalytic function of cathepsin D in the heart. But the period after the stress accompanied by the consecutive proteolysis rate reduction, that can be explained, probably, by a change in enzyme conformation. The concentration of Ca2+ (10(-6), 10(-5) M) and cAMP (10(-7), 10(-6) M) exert a regulating influence on the cathepsin D activity in the heart in acute stress period and after it.     

The effect of "social stress" during rat pregnancy on the anxiety level of the progeny

Anxiety and locomotion were studied in offsprings of female rats subjected to everyday stress (one a day being displaced into another cage with pregnant rats) during the 3d stage of pregnancy. At the age of 1 month, the prenatally stressed rats had higher anxiety and lower locomotion in comparison with control animals. At the age of 3 month, the prenatally stressed females did not significantly differ from the control in the level of anxiety and locomotion, while the males demonstrated lower ambulation than the control animals.     

The effects of enalapril maleate and cold stress exposure on tyrosine hydroxylase activity in some rat tissues

Enalapril is a highly specific and competitive inhibitor of angiotensin-I converting enzyme (ACE) and thus belongs to the category of ACE inhibitors. The beneficial effects of ACE inhibitors appear to result primarily from the suppression of the plasma renin-angiotensin-aldesterone system. This study was designed to detect the effects of enalapril maleate and cold stress on tyrosine hydroxylase (TH) activity in adrenal medulla, heart and hypothalamus in rat. In cold stress treatment (exposed to 8 degrees C cold for 48 h) TH activity was found to be raised significantly (p < 0.05) in adrenal medulla, hypothalamus and heart tissues. In the adrenal medulla, hypothalamus and heart tissues, TH activity of enalapril maleate treated rats (10 mg kg(-1) body weight) group was not raised significantly (p > 0.05). Following intraperitoneal injection of enalapril maleate (10 mg kg(-1) body weight) the rats were exposed to 8 degrees C cold for 48 h. After cold stress and enalapril maleate treatment no statistically significant change in tyrosine hydroxylase activity was detected in adrenal medulla, hypothalamus or heart (p > 0.05). The results of our studies show that enalapril maleate blocks the effect of cold stress on the regulation of TH activity.     

The effect of adrenaline and acetylcholine on the hypothalamic-hypophysial neurosecretion in the rat

Summary The present investigation was undertaken to study the effects of adrenaline and acetylcholine on the hypothalamic-hypophysial neurosecretory system in rats.The drugs were injected intraperitoneally and into the lateral brain ventricle. The water diuresis was measured (I group). The animals were killed 45 min after intraperitoneal and 20 min after intraventricular administration of the drugs for the histological observations on the neurosecretory system and the histochemical studies of catecholamines in this area (II group).The antidiuretic effect of adrenaline and acetylcholine was established. The antidiuresis was more remarkable following intraventricular treatment.There was no direct relationship between the amount of neurosecretory substance and ADH activity in the posterior pituitary in the short term experiment after intraperitoneal administration of these drugs.The rapid release of ADH from the posterior pituitary was accompanied with a remarkable output of neurosecretory substance from the neurosecretory cell bodies into the axons and these effects were considerable after intraventricular introduction of the drugs. Some neurosecretory cells in the state of the initial hyperfunction were observed. In the posterior pituitary the initial mobilisation of the neurosecretory material from the neurosecretory terminals following intraventricular introduction of the drugs was observed.The supraoptic nucleus seems to be more sensitive to acetylcholine and the paraventricular nucleus to adrenaline treatment.The significant vasodilatation in the posterior pituitary and in the area of the supraoptic nucleus following intraventricular acetylcholine introduction was established.According to the data described it is possible to expect the existence of control of the hypothalamic neurosecretory activity by means of adrenergic and cholinergic structures.I am very obliged to Prof. W. Bargmann for his stimulating interest in this Study. I am grateful to Dr. G. Leontieva and Dr. V. Govyrin for the possibility to use the fluorescence catecholamine method, to Dr. E. Zeimal and Prof. M. Michelson for using the method for intraventricular injections.     

Changes in the protein level in rat hippocampal neurons during development of the alimentary conditioned reflex under normal conditions and after treatment with iproniazid

The protein content in neurons of areas CA-1 and CA-3 of the dorsal hippocampus has been determined by means of cytointerferometry in rats during elaboration of unlocal alimentary instrumental reflex (ULAIR) and local alimentary instrumental reflex (LAIR) on the background of increased and normal serotonine content in the brain. It has been found that during the ULAIR elaboration the hippocampal neurons react by an increase of dry mass, during the LAIR elaboration-by its decrease. Under condition of serotonine excess in the brain the changes of dry mass in hippocampal neurons during elaboration of the two reflexes are opposite to these observed during the ULAIR and LAIR elaboration with normal serotonine content.