Lipid peroxidation and antioxidant enzymes in the brain of rats exposed to acute emotional stress: Effect of interleukin-1β

Acute emotional stress is shown to raise the level of malonic dialdehyde in the hypothalamus of August rats. After intraventricular administration of interleukin-1β, the malonic dialdehyde level and the activity of antioxidant enzymes tended to rise selectively in the hypothalamus (but not in the sensorimotor cortex) of August, Wistar, and WAG rats. In the presence of this interleukin, acute emotional stress did not cause increases in lipid peroxidation products in the hypothalamus of August rats. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 120, N ^o 9, pp. 244–247, September, 1995     

Gastric mucosal lesions caused in rats of different strains by emotional stress,and the protective effect of interleukin 1β

Acute emotional stress results in damage to gastric mucous membranes in August, Wag, and particularly Wistar rats. The damage is less severe in rats preinjected with inter-leukin 1β into a lateral ventricle of the cerebrum. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 117, N ^o 3, pp. 238–239, March, 1994     

Morphological manifestations of hereditary hypertrophic cardiomyopathy in W/SSM rats

A W/SSM strain of rats with hereditary hypertrophic cardiomyopathy has been created by inbreeding Wistar rats selected for an increased, sensitivity to the cataractogenic effect of high doses of galactose. It is shown that myocardial hypertrophy attended by a diffuse stroma collagenization, focal sclerotic changes, and signs of, chronic heart failure spontaneously develops in these animals. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 118, N ^o 8, pp. 203–207, August, 1994     

Role of mast cells in reparative processes in inflammation

Using the model of acute infectious peritonitis in rats, it is shown that inflammation induced in the absence of mast cells is characterized by marked inhibition of reparative processes. The most significant accumulation of functionally active fibroblasts and the development of granulations and young connective tissue in the mesentery occur 5–10 days after flogogen injection in the natural development of inflammation and after 10–20 days in the absence of mast cells. The data suggest that under natural conditions mast cells directly or indirectly stimulate reparative processes. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 119, N ^o 3, pp. 262–265, March, 1995 Presented by E. D. Gol'dberg, Member of the Russian Academy of Medical Sciences     

Ulcerative gastric lesions in august and wistar rats: Effects of acute emotional stress

Wister rats, but not August rats, developed ulcerative lesions in the gastric mucosa as a results of exposure to severe emotional stress caused by immobilization in closed tubes submerged in water. In addition, the stressed rats of both strains showed an increased ratio of thymus weight and a decreased ratio of adrenal weight to body weight. It is concluded that emotionally stressed Wistar, but not August, rats are prone to develop ulcerative gastric lesions. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 120, N ^o 11, pp. 469–470, November, 1995 Presented by K. V. Sudakov, Member of the Russian Academy of Medical Sciences)     

Comparative analysis of polypeptides in the heat shock proteins synthesized in the myocardium of Wistar and August rats

The use of two-dimensional electrophoresis to study the polypeptide composition of heat shock proteins 70 synthesized in the myocardium of Wistar and August rats in response to thermal stress and repetitive immobilization stress revealed interstrain differences in the composition of stimulated polypeptides in these proteins. The differences are mainly due to differential expression of the heat shock protein gene(s) encoding polypeptides with pI 6.2–6.0 in the two strains. The drastically reduced levels of the synthesis and/or accumulation of some heat shock proteins 70 in the hearts of August rats are associated with their failure to develop cardioprotective phenomena in response to repetitive immobilization stress. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 120, N ^o 7, pp. 30–32, July, 1995 Presented by R. S. Karpov, Member of the Russian Academy of Medical Sciences     

Differences in behavioral patterns and resistance to stress-induced gastric ulceration between August and Wistar rats adapted and unadapted to hypoxia

The incidence of gastric ulceration induced by acute emotional stress in Wistar rats is 3 times higher than in August rats, and the mean number of gastric ulcers in Wistar rats 6.3-fold surpassed that in August rats. Wistar rats predisposed to stress-induced ulceration displayed suppressed locomotor and exploratory activities in the open field test, while August rats had more stable behavioral patterns and enhanced exploratory activity after stress. Short-term preadaptation to hypobaric hypoxia for 6 days attenuated stress-induced gastric ulceration, whereas long-term adaptation (40 days) aggravated the severity of gastric ulcers in August and Wistar rats. The interstrain differences in stress-induced ulceration persisted after adaptation. The data suggest that these differences are related to genetically determined peculiarities of production and metabolism of NO and glucocorticoids in August and Wistar rats. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 128, No. 12, pp. 638–641, December, 1999     

Effect from prophylactic administration of pentoxyphylline (trental) on the development of neuropathic pain syndrome and on the associated microcirculatory disturbances

Prophylactic injection of pentoxyphylline into rats with a neuropathic pain syndrome produced by sciatic nerve transection delayed and weakened the development of this syndrome, improved the microcirculation and venular permeability, and reduced mast cell degranulation. The findings of this study recommend pentoxyphylline for clinical use in the multidrug treatment of neuropathic pain syndromes. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 119, N ^o 5, pp. 485–487, May, 1995 Presented by G. N. Kryzhanovskii, Member of the Russian Academy of Medical Sciences     

Protein content in rat brain neurons predisposed and resistant to emotional stress

Protein content was measured by interferometry in the cerebral neurons of August rats predisposed to emotional stress and Wistar rats resistant to it. Protein content was 16–18% lower in the neurons of the third and fourth layers of the sensorimotor cortex and 51% higher in the caudate nucleus neurons (cerebral subcortical nodes) of August rats than in Wistar rats. This indicates an inversion in protein distribution in the cortex and subcortex of August rats which are characterized by typical protein content in different types of neurons and apparently by peculiar cerebral structure and function. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 126, No. 10, pp. 477–480, October, 1998     

Role of adrenocorticotropic hormone in the activation of heparin secretion by mast cells in stressed rats

A morphometric analysis of mast cell populations in the subcutaneous tissue and mesentery from rats demonstrated stimulation of heparin secretion by adrenocorticotropic hormone. Thirty minutes after the administration of this hormone to unstressed rats, the functional stutus of mast cells did not differ from that of such cells from rats stressed by being immobilized for 30 min after receiving physiological saline instead of the hormone. In contrast, the 30-minute immobilization failed to elicit an adequate secretory response from the mast cells of rats in which the release of adrenocorticotropic hormone had been blocked by dexamethasone. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 120, N ^o 10, pp. 349–351, October, 1995 Presented by I. P. Ashmarin, Member of the Russian Academy of Medical Sciences     

Potassium and sodium ions in the nerve tissue of emotionally overstrained rabbits

Measurement of K⁺ and Na⁺ concentrations in samples of individual brain nuclei and in ganglia of the autonomic nervous system from rabbits subjected to severe emotional stress (ES) through aperiodic stimulation of ventromedial hypothalamic nuclei and electrocutaneous stimulation revealed significantly altered levels of these ions in locus ceruleus samples from animals predisposed to ES-induced cardiovascular disorders and in samples of neurons of the caudal part of the brainstem from those resistant to such disorders. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 118, No 8, pp. 129–131, August, 1994 Presented by K. V. Sudakov, Member of the Russian Academy of Medical Sciences     

Morphology of the accessory (pharyngeal) adenohypophysis and its relationship with the pharyngeal tonsil in the human fetus

The pharyngeal pituitary was examined in human fetuses during weeks 16 to 32 of development by light microscopy with routine and histochemical treatment of slices. All the fetuses examined possessed a pharyngeal pituitary, which develops from the epithelium of the upper pharyngeal wall, just like the main pituitary. Rathke's pouch becomes transformed into a cord and grows towards the midbrain forming the hypophysis cerebri, while some cells at the base of the cord remain in the integumentary epithelium of the pharynx and give rise to the pharyngeal pituitary. This organ represents a group of long epithelial cords under the integumentary epithelium within the connective tissue of the pharyngeal mucosa. The cords contain light and dark cells with signs of a secretory cycle. The pituitary cords grow into the lymphoid tissue of the pharyngeal tonsil. The integumentary epithelium does not contain protective structures at the site of origin of the pharyngeal pituitary. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 120, N ^o 8, pp. 211–214, August, 1995 Presented by N. K. Permyakov, Member of the Russian Academy of Medical Sciences     

Adaptation to multiple electrostimulation limits hemorrhages in the brain of rats with audiogenic epilepsy

Exposure of Krushinsky-Molodkina rats (a strain genetically predisposed to audiogenic epilepsy) to multiple electrostimulation (a course consisting of 10 sessions) prolongs the latency of epileptic seizures, lowers blood levels of stress hormones, lessens the severity of seizures, and reduces by half the area occupied by subdural hemorrhages. It is concluded that the major role in the mechanism of these protective effects is played by adaptation to stress, accompanied by the accumulation in the brain of heat-shock proteins that stabilize cellular structures. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 117, N ^o 2, pp. 127–129, February, 1994     

Adaptive stabilization of structures and adaptive protection of the heart in rats of two different genetic strains: Role of heat-shock proteins hsp 70

Periodic exposures of Wistar rats to a stressor resulted in the accumulation of five isoforms of heat-shock proteins (hsp70) in their myocardia and, as a consequence, in increased resistance to thermal damage shown by their isolated hearts, whereas in rats of the August strain such exposures did not lead to hsp70 accumulation and the heart's resistance was not increased. It is concluded that the ability of a given genetic strain to develop adaptive protection of the heart appears to depend on the ability of that strain to boost the expression of hsp70 genes in response to stressors. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 118, N ^o 8, pp. 126–129, August, 1994 Presented by N. R. Paleev, Member of the Russian Academy of Medical Sciences     

Aldosterone binding with corticosteroid brain receptors in rats: Effect of behavioral typology and stress

Differences in³H-aldosterone binding with hippocampus cytosol receptors were found to be dependent on the behavioral type of male Wistar rats in the “emotional resonance” test. These differences were not observed in the cytosol analysis of the remaining part of the brain. Control rats and rats subjected to short-term stress by painful electrical stimulation showed a long-term drop of³H-aldosterone binding with hippocampus cytosol in active as compared to passive animals preferring a closed space. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 120, N ^o 7, pp. 49–51, July, 1995 Presented by I. P. Ashmarin, Member of the Russian Academy of Medical Sciences     

Antiulcerogenic effects of benzylpenicillin in acutely stressed rats

The antibiotic benzylpenicillin was found to produce dose-dependent antiulcerogenic effects in rats when administered immediately before their exposure to acute stress (swimming for 1 h) that led to gastric mucosal ulceration. Such effects were not observed in rats given benzylpenicillin 48 h before stress exposure. The results of this study suggest that in acutely stressed animals benzylpenicillin may activate as yet unidentified mechanisms which afford protection to the gastric mucosa and which are not associated with the longer-lasting antimicrobial effects of this antibiotic. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 118, N ^o 8, pp. 131–133, August, 1994     

Catecholamines in the adrenals of August and Wistar rats with acute emotional stress

Acute emotional stress caused by immobilization and cutaneous electrical stimulation increases the relative weight of adrenals in Wistar rats and decreases it in August rats. The epinephrine and norepinephrine contents of the adrenals in control and stressed August rats are higher than in Wistar rats. Acute stress lowers the levels of these biogenic amines in the adrenals of both strains, particularly in Wistar rats. The left adrenal gland of control and stressed August rats, but not of Wistar rats, has a higher content of biogenic amines than the right, and both adrenals of stressed August rats contained higher dopamine concentrations than those of stressed Wistar rats. Presumably, epinephrine and norepinephrine are resynthesized in the adrenals of stressed August rats at higher rates than they are released from these glands, while the adrenals of Wistar rats respond to stress by rapidly releasing these catecholamines and resynthesizing them at a slow rate. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 123, No. 6, pp. 645–648, June, 1997     

Reaction of myocardial mast cells during neoangiogenesis induced by YAG:Nd laser

Time course of morphofunctional changes in myocardial mast cells of Wistar rats irradiated with a YAG:Nd laser is studied. Mast cells were detected on serial sections by toluidine blue staining. A drastic increase in mast cell degranulation around the laser channel was observed on days 1–20 of experiment. Mast cell degranulation may be the first stage in neoangiogenesis in the myocardium in response to laser injury. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 126, No. 7, pp. 116–118, July, 1998     

Effect of interferon on the structural organization of rat thymus

Changes in the thymus of male Wistar rats were studied under a light microscope at various times after intranasal administration of α-interferon. The relative mass of the organ, the cortex volume, the total number of cells, the number of small and medium lymphocytes, and the number of mitoses decrease 14 days after interferon administration. At the same time, the number of macrophages, neutrophils, mature plasmacytes, eosinophils, and erythrocytes increases, and mast cells appear. Thus, α-interferon probably suppresses the formation of T cells, facilitates allergization of the organism, and increases the permeability of the vascular endothelium. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 118, N ^o 12, pp. 609–612, December, 1994     

Variation in plasma morphine level and pain sensitivity in prenatally morphinized rats

It is established that mature random-bred and Wistar rats exhibit the same level of pain sensitivity in the tail-flick test, but the analgetic effect of morphine (5 mg/kg) is variously expressed: marked hypalgesia is observed in mongrel but not in Wistar rats. Prenatal morphinization enhances the analgetic effect of morphine in both mongrel and Wistar rats. There is a direct correlation between the plasma morphine content in prenatally morphinized rats and their sensitivity to the analgetic action of morphine. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 120, N ^o 9, pp. 273–275, September, 1995 Presented by D. A. Kharkevich, Member of the Russian Academy of Medical Sciences