[Biogenic amines in the brain structures of rats from genetically diverse strains under stress]. / Biogennye aminy struktur mozga krys geneticheski razlichnykh linii v usloviiakh stressa.

The content was studied of biogenic amines and their metabolites (by the method of high-effective fluid chromatography electrochemical detection) in the reticular formation of the midbrain, locus coeruleus and sensorimotor cortex in the rats of Wistar and August lines, differing in the behaviour in the open field, in conditions of immobilization stress. The dependence was revealed of the biogenic amines level on the animals genotype and individual characteristics. Most probably, the level of biogenic amines metabolism in central brain structures determines the stability of the animals against emotional stress.

[Immobilization stress-induced changes in catecholamine levels in the individual cerebral nuclei in rats of different zoosocial ranks]. / Vyzvannye immobilizatsionnym stressom izmeneniia urovnia katekhola- minov otdel'nykh iader mozga krys, razlichaiushchikhsia po zoo- sotsial'nomu rangu.

Immobilization stress induced catecholamines level changes were studied in brain nuclei, taking part in blood pressure central regulation in rats with different zoosocial position. The significant differences in catecholamines level between the zoosocial groups of rats were shown in dopamine synthesized hypothalamic nuclei-n. arcuatus, n. periventricularis and noradrenaline synthesized-n. subcoeruleus++. The dominant rats were characterized by the highest catecholamines level.

[Morphofunctional changes in brain neurons during emotional stress]. / Morfofunktsional'nye izmeneniia neironov mozga v usloviiakh émotsional'nogo stressa.

It is shown that the strong emotional immobilization stress in rats resulted in increased blood-brain barrier permeability and besides--in brain parenchymal vessels damages accompanied by haemorrhages and the loss of some nerve cells. The earliest and strongest brain vessel disruptions under emotional stress were found in the oral part of the brain stem reticular formation. The vessel disturbances and the damages of the neurons were found for a long time interval after immobilization stress and resulted in functional, behavioral changes and immune reactions. Locus ceruleus was found to be involved in the blood-brain barrier function regulation and due to the fact in the fortune of the neurons under the emotional stress.

[Immobilization stress-induced lesions of structures of the midbrain reticular formation]. / Vyzvannye immobilizatsionnym stressom povrezhdeniia struktur retikuliarnoi formatsii srednego mozga.

Emotional stress in rats resulted in blood-brain barrier increased permeability and brain parenchymal vessel disruptions. Stress induced microvascular damages were mainly observed in midbrain reticular formation. In this article the components of midbrain reticular formation were studied 1, 2, 4 and 6 weeks after immobilization stress. The destructive changes in some neurons, glia cells and myelin fibers were shown up to 6 weeks after immobilization. The signs of the recovery were also observed. It was supposed that the brain parenchymal vessel damages under emotional stress were due to the stress induced locus coeruleus dysfunctions.

[Structural bases of the induction of immune reactions in emotional stress]. / Strukturnye osnovy induktsii immunnykh reaktsii pri émotsional'nom stresse.

Immobilization stress in rats can provoke damages of the brain parenchymal vessels, which are most pronounced in the reticular formation of the midbrain. In this case the blood plasma and cells enter the brain and the blood elements of brain tissue enter the circulation. Some experimental animals exhibit the serum complement-fixing brain antibodies and specific reactions of basophils to brain antigens 14 days after exposure to stress. Most of the rats reveal immune reactions and neurosensitivity a month later. Some of them exhibit the autoantibodies to norepinephrine and serotonin. It is suggested that stress-induced brain vascular damages may play an important role in the mechanisms of immune reaction induction.

[The role of catecholamines in various brain nuclei in maintaining the stability of physiological functions in emotional stress]. / Rol' katekholaminov otdel'nykh iader mozga v podderzhanii ustoichivosti fiziologicheskikh funktsii pri émotsional'nom stresse

Direct arterial BP recording through an indwelling catheter in the tail artery showed August rats to be more prone to disorders of arterial BP control under emotional stress, as compared to Wistar rats. High baselines of catecholamines, dopamine in particular, in the cerebral nuclei, and the involvement of zone A1 adrenalin BP control are unfavorable indicators of a predisposition to abrupt BP changes in response to stress. Locus ceruleus is shown to play an essential role in BP control under emotional stress, its functions being largely determined by genetic mechanisms.

[Open-field behavior of rats following bilateral coagulation of the locus coeruleus]. / Povedenie krys v otkrytom pole posle bilateral'noi koaguliatsii sinego piatna.

A modified open-field test was used in the experiments on rats. It was shown that animals 6 days after bilateral coagulation of locus coeruleus displayed weight changes and some behavioural parameters distinct from those of sham-operated and control animals. The most pronounced differences observed in animals after locus coeruleus coagulation, as compared to the control, were inversion and adaptive responses to a sudden brief stimulus, locomotor dysfunction and absence of response to handling.

[Allergic encephalomyelitis in guinea pigs on the intracutaneous and subcutaneous administration of fragment 114-122 of the human myelin cationic protein]. / Allergicheskii éntsefalomielit u morskikh svinok pri vnutrikozhnom i podkozhnom vvedenii fragmenta 114-122 kationnogo belka mielina cheloveka.

Single intracutaneous injection of 30 micrograms of human basic myelin protein peptide 114-122 (H-Phe-Ser-Trp-Gly-Ala-Glu-Gly-Gln-Arg-OH) with Freund adjuvant induced the onset of encephalomyelitis on day 9-19 after the injection. The lethality was 33%. In autumn the disease was more severe than in summer.

[Changes in the catecholamine content of brain structures in rats subjected to immobilization stress]. / Izmeneniia soderzhaniia katekholaminov v strukturakh mozga krys, perenesshikh immobilizatsionnyi stress.

The changes in DOPA and catecholamine (adrenaline, noradrenaline, dopamine) levels were investigated in noradrenaline- and dopamine-synthesizing brain nuclei of Wistar rats after prolonged immobilization stress on catecholamine analyzer (BAS, USA) using HPLC technique. Distinct DOPA and catecholamine changes were observed in locus ceruleus + nucleus subceruleus (1. c + n. sc) and substantia nigra at any stage after immobilization (right after immobilization and 15 and 30 days later). The most prominent alterations in noradrenaline content were detected in 1. c + n. sc. 30 days after immobilization NA level in these nuclei was 1.5 times higher, as compared to the control one. It is suggested that the increasing noradrenaline level in 1. c + n. sc. plays a defensive role in survival of rats after immobilization stress.

[Lactate dehydrogenase isoenzyme spectrum in various areas of the reticular formation of the brain in rats: the effect of emotional stress]. / Izofermentnyi spektr laktatdegidrogenazy v razlichnykh otdelakh retikuliarnoi formatsii mozga krys: vliianie émotsional'nogo stressa.

The changes in lactate dehydrogenase (LDG) isoenzyme content in the various brain areas were studied in intact Wistar rats and upon immobilization stress. LDG fraction levels were compared to BP changes during immobilization. The proportion of "anaerobic" LDG fractions was higher and the proportion of "aerobic" fractions lower in the dorsal area of midbrain substantia reticularis than in medulla oblongata reticular formation. The changes in LDG fraction content related to BP alterations during immobilization were observed in dorsal and ventral areas of midbrain (but not medulla oblongata) substantia reticularis. The proportion of anaerobic LDG4 fraction in the dorsal area of midbrain substantia reticularis was higher in rats with hypertensive responses, than in hypotensive animals. The changes in LDG5 fraction content were opposite. In the ventral area of midbrain reticular formation BP reduction was accompanied by a significant rise in "anaerobic" and a decrease in "aerobic" LDG fraction levels. The data obtained indicate certain differences in the intensity of aerobic and anaerobic processes of carbohydrate degeneration in various areas of substantia reticularis in control rats, as well as the correlation of changes in energy metabolism in the brain with BP alterations during emotional stress.

[Locus ceruleus: the regulation of hemato-encephalic barrier function normally and under emotional stress]. / Locus ceruleus: reguliatsiia funkstii gematoéntsefalicheskogo bar'erav norme i v usloviiakh émotsional'nogo stressa.

To study the role of locus ceruleus in maintaining the blood-brain barrier function in conditions of emotional stress, the blood-brain barrier permeability was estimated after locus ceruleus damaging with DSP4 (N-2-chloroethyl-N-ethyl-2-bromobenzylamine). The importance of locus ceruleus for the integrity of blood-brain barrier functions in control animals and especially in rats exposed to emotional stress was revealed. The data obtained prove the homeostatic role of locus ceruleus, which is the most prominent in conditions of emotional stress.

[Catecholamines in nuclei of the brains of the August strain rat during immobilization stress]. / Katekholaminy v iadrakh mozga krys linii Avgust pri immobilizatsionnom stresse.

Changes in epinephrine, norepinephrine and dopamine levels in different brain nuclei of the August rats were studied after 6.5-hr immobilization. The linkage between the BP dynamics under emotional stress and changes of catecholamines content was observed in epinephrinsynthetizing area A1, norepinephrinsynthetizing area A6 (locus Coeruleus) and dopaminsynthetizing area A9 (substantia nigra). Sharp increase of the BP in the August rats was related to obvious decrease of epinephrine content in A1, norepinephrine in locus coeruleus and dopamine in substantia nigra. The data obtained suggest that deficit of the catecholamines due to the metabolic changes during emotional stress may result in distutbances of the cardiovascular functions control in the August rats.

[Emotional stress-induced changes in catecholamines in the nuclei of the brains of rats differing in "open-field" behavior]. / Vyzvannye emotsional'nym stressom izmeneniia katekholaminov v iadrakh mozga krys, razlichaiushchikhsia po povedeniiu v "otkrytom pole".

The open-field test was used to study the role of initial emotionality in participation of brain catecholamines (CAs) in the BP control under emotional stress. The rats different in emotionality differed from each other in the level of CAs in single brain nuclei under normal conditions. Under stress, opposite CAs changes occurred in rats differing by their initial emotionality, in noradrenaline-synthetizing brain nuclei only. The neurochemical processes (features) which took part in the central BP control under stress were different in rats differing in their initial emotionality.

[Acetylcholinesterase and choline acetyltransferase in the nervous system of rabbits predisposed to cardiovascular disorders under emotional stress]. / Atsetilkholinésteraza i kholinatsetiltransferaza v nervnoi sisteme krolikov, predraspolozhennykh k narusheniiu serdechno-sosudistykh funktsii pri émotsional'nom stresse.

A study was made of the activity of acetylcholinesterase (AChE), cholinacetyl transferase (CAT), butyril cholinesterase (BCE) and water-soluble proteins in the structures of the CNS and in the autonomous ganglia in rabbits predisposed to cardiovascular disorders under emotional stress. It was established that unlike resistant animals, in those predisposed to cardiovascular disorders, the CAT content in the periphornical area of the hypothalamus did not differ from the control, the content of water-soluble proteins in the CNS structures and the ganglia remained unchanged either as compared with the control. The authors assume that the data obtained confirm a previously advanced concept of the involvement of the cholinergic system of the periphornical area of the hypothalamus in the maintenance of the stability of cardiovascular functions by regulation of the water-salt metabolism.

Strain differences in brain biogenic amines concentration in rats with different resistance to emotional stress.

Blood pressure and heart rate were measured under the conditions of prolonged emotional stress due to 30 h immobilization in rats of various strain: 1. Wistar; 2. Veg (deviated from Wistar); 3. August; 4. Bastards. Some defined areas of brain from Wistar and August rats were dissected and used for the estimation of noradrenaline (NA) and dopamine (DA) content with the aid of spectrofluorimetric method. It was found that, among the animals of all strains used, different groups may be defined according to their resistance to cardiovascular changes due to emotional stress. Thus, the highest percentage of resistant animals was found among Wistar rats, while the lowest one occurred in August animals. Intact August rats differ from those of Wistar strain by a lower content of NA in hypothalamus and a higher content of DA in midbrain and isthmus. Sensitive animals of August strain showed an increase of DA content in hypothalamus and bulb compared to intact animals and a decrease of DA content compared to operated controls, while no such changes were observed in Wistar rats. However, sensitive Wistar rats showed an increase of DA content in midbrain.

[Monoamine oxidase activity in rabbit brain nuclei in experimental acute emotional stress]. / Aktivnost' monoaminoksidazy v iadrakh mozga krolika v usloviiakh ostrogo éksperimental'nogo émotsional'nogo stressa.

Activity of monoamine oxidase in the neurons of catecholamine-synthesizing nuclei of hypothalamic and brainstem of rabbits with different resistance of cardiovascular functions to emotional stress was studied by the Glenner et al. method. An acute experimental emotional stress was induced by non-periodic electric stimulation of the hypothalamic ventromedial nucleus and the skin in immobilized adult chinchilla rabbits. It was found that monoamine oxidase activity in the neurons of groups A5, A6, A7 and A14 under acute experimental emotional stress increased in rabbits "resistant"to stress and remained unchanged in rabbits "predisposed" to stress. The activity of monoamine oxidase in the neurons of group A12 remained unchanged in the rabbits "resistant"to stress and decreased in the rabbit "predisposed" to stress.