[Effects of desensitization of capsaicin-sensitive afferent neurons on gastric microcirculation in rats depend on the blood glucocorticoid hormone level].

The effects of desensitization of capsaicin-sensitive afferent neurons on gastric microcirculation were investigated before and after administration of indomethacin at ulcerogenic dose in adrenalectomized rats with or without corticosterone replacement and in sham-operated animals. We estimated the blood flow velocity in submucosal microvessels; the diameters and permeability of mucosal venous microvessels as parameters of gastric microcirculation. Desensitization of capsaicin-sensitive neurons was performed with capsaicin at the dose 100 mg/kg two weeks before the experiment. Adrenalectomy was created one week before experiment. In vivo microscopy technique for the direct visualization of gastric microcirculation and the analysis of the blood flow was employed. Indomethacin at ulcerogenic dose decreased the blood flow velocity in submucosal microvessels, caused dilatation of superficial mucosal microvessels and increased their permeability. Desensitization of capsaicin-sensitive afferent neurons potentiated indomethacin-induced microvascular disturbances in gastric submucosa-mucosa. These potentiated effects of the desensitization are obviously promoted by concomitant glucocorticoid deficiency. Thus, glucocorticoid hormones have a beneficial effect on gastric microcirculation in rats with desensitization of capsaicin-sensitive afferent neurons.

[The effects of desensitization of capsaicin-sensitive neurons on the blood flow in microvessels of the rat gastric serous muscular membrane with normal and insufficient contents of glucocorticoids].

The effects of desensitization of capsaicin-sensitive neurons on the blood flow velocity in microvessels of the gastric muscular membrane were investigated before and after indomethacin (35 mg/kg) administration in adrenalectomized rats with or without corticosterone replacement (4 mg/kg sc) and in sham-operated animals. Desensitization of capsaicin-sensitive neurons was performed with neurotoxic dose of capsaicin (20 + 30 + 50 mg/kg sc) two weeks before the experiment. Adrenalectomy was created one week before the experiment. The in vivo microscopy technique for direct visualization of gastric microcirculation and analysis of red blood cell (RBC) velocity was employed. Indomethacin decreased the RBC velocity. Adrenalectomy by itself profoundly decreased the RBC velocity, whereas corticosterone replacement prevented this effect. Desensitization of capsaicin-sensitive neurons did not influence the RBC velocity in sham-adrenalectomized rats; however, it induced further fall of both basal and indomethacin-induced RBC velocity in adrenalectomized rats that was prevented by corticosterone. We conclude that glucocorticoid hormones have a beneficial effect on the blood flow velocity in microvessels of the gastric muscular membrane in rats with desensitization of capsaicin-sensitive neurons.

[Characteristics of heterochromatin of heterophase nuclei from interphase neurons of various brain structures selected for the nervous system excitability]. / Kharakteristika geterokhromatina interfaznykh iader neironov razlichnykh struktur golovnogo mozga krys, selektirovannykh po vozbudimosti nervnoi sistemy.

Quantitative characteristics (the area and number of chromocenters) of the interphase C-heterochromatin in the nuclei of pyramidal neurons of the midbrain reticular formation, sensorimotor cortex, and hippocampus (CA3) of rat strains with different genetically determined excitability were studied in the normal state of the animals and after exposure to a short-term emotional pain stress. The results indicate a relationship between the excitability of the nervous system and structural-functional state of the neuronal interphase heterochromatin. The role of cytogenetic features of different brain structures in the CNS functioning and behavior and their relation with genetically determined excitability of the nervous system are discussed.

[Proliferative activity and structure-functional organization of chromosomes in cells from the developing brain in respect to genetically determined excitability of the rat nervous system]. / Proliferativnaia aktivnost' i osobennosti strukturno-funktsional'noi organizatsii khromosom v kletkakh razvivaiushchegosia mozga v sviazi s geneticheski determinirovannoi vozbudimost'iu nervnoi sistemy u krys.

Neuroblasts of developing hippocampus of 16-17-day old rat embryo of the line with high threshold excitability are characterised by a high level of proliferative activity and chromosome aberration, as well as high degree of brain chromatin concentration as compared with embryos of a line with low threshold excitability.

[Microcirculation in the skeletal muscle of the white rat subjected to deep immersion hypothermia and restored by self-warming]. / Mikrotsirkuliatsiia v skeletnoi myshtse beloi krysy, podvergnutoi glubokoi immersionnoi gipotermii i vosstanovlennoi samorazogrevaniem.

The immersion hypothermia increased the blood flow at the initial stage, which was followed by a decrease in the capillary blood flow. In subsequent self-warming of the white rats the blood flow velocity was restored to practically initial values. No irreversible changes seem to occur in the rat muscle microcirculation system in a deep hypothermia.

[Disorder and restoration of the microcirculation in the brain of rats under deep hypothermia]. / Narushenie i vosstanovlenie mikrotsirkuliatsii v mozgu krys pri glubokoi gipotermii.

Sharp deceleration of the brain microcirculation in deep hypothermia (up to 16-18 degrees C in the rectum) is due to no irreversible alterations in the microcirculation system. Physiological controlling mechanisms of this function are preserved and help to restore the velocity of the capillary blood flow in the course of warming up of the animal.

[The adaptation-protective effect of corticosteroids on the rat gastric mucosa and its mechanism]. / Adaptatsionnyi zashchitnyi éffekt kortikosteroidov na slizistuiu obolochku zheludka krys i ego mekhanizm.

The influence of stress-induced corticosteroid production on gastric ulceration, blood flow velocity in gastric microvessels and blood pressure was studied in rats. The role of plasma corticosteroids was investigated by means of blockade of the pituitary-adrenocortical system (PACS) and following corticosterone replacement therapy (400 mu/100 g b.w.). The blockade which was induced by Fi. hydrocortisone administration (7 days before stress, 30 mg/100 g b. w.) resulted in an insufficient corticosteroid production. To evaluate the influence of corticosteroids on blood flow velocity in gastric microvessels of muscular, submucosal and mucosal coats it was used intravital microfilming by means of a dark-field contact epiobjective. Stress (water immersion + restraint) induces an ulceration, a decrease in the systemic arterial blood pressure (3 h after stress onset) and a decrease in blood flow velocity in the gastric microvessels (3 h after stress onset). In rats with insufficient corticosteroid production stress-induced ulceration, a decrease in blood pressure and gastric blood velocity were more greater than in rats with intact PACS. Replacement corticosterone therapy corrected all parameters. The results revealed that antiulcerogenic effect of stress-induced glucocorticoid production is realised owing to normalisation of gastric blood supply which is provided by an increase in systemic blood pressure.

[The antiulcer effect of corticosteroids and the blood flow in the gastric mucosa]. / Protivoiazvennyi éffekt kortikosteroidov i krovotok v slizistoi obolochke zheludka.

Intravital microfilming by means of dark-field contact epiobjective was used for investigation of the role of gastric microcirculation in antiulcerogenic action of corticosteroids in rats. Microvascular volume blood flow velocity was calculated from measurements of red cell velocity and vessel diameters. There was compared gastric submucosal and mucosal microcirculation as well as gastric ulceration after water-immersion stress in rats with normal function of hypothalamo-pituitary-adrenocortical (HPA) axis and in rats with insufficiency of corticosteroid production, induced by blockade of the HPA axis. The 3h stress induced gastric ulcerations, dilatation of mucosal microvessels and a significant decrease of volume blood flow in submucosal microvessels. These changes were greater in rats with blockade of HPA axis than in animals with normal corticosteroid production. Replacement corticosterone therapy decreased the effects of HPA axis blockade. Thus corticosteroids which are produced during stress restricted the reduction of volume blood flow in submucosal microvessels, the dilatation of mucosal microvessels as well as gastric ulcerations. These findings indicate that corticosteroids exert their antiulcerogenic action via the mechanism of improvement of gastric microcirculation.

[Corticosteroids limit the decrease in blood flow velocity in the microvessels of the gastric submucosal layer during stress in rats]. / Kortikosteroidy ogranichivaiut snizhenie skorosti krovotoka v mikrososudakh podslizistogo sloia zheludka pri stresse u krys.

To evaluate the influence of stress and corticosteroids on blood flow velocity in gastric submucosal microvessels it was used intravital microfilming by means of a dark-field contact epiobjective. The plasma filled "gap" in the continuous erythrocyte flow were used as the markers to measure linear blood flow velocity. In unstressed rats the linear blood flow velocity was equal to 2.0 +/- 0.08 mm/sec (156 microvessels, 6.4 +/- 0.14 micron in diameter), calculated volume blood flow--(6.9 +/- 0.48) x 10(-5) microliters/sec. Stress (water immersion and restraint) led to a decrease of blood flow velocity in microvessels to more than double. A stress-induced decrease of blood flow velocity was more greater in rats with insufficient corticosteroid production. The linear velocity of blood flow of these rats was lowered to 0.6 +/- 0.06 mm/sec, volume blood flow to (1.6 +/- 0.21) x 10(-5) microliters/sec. Replacement corticosterone therapy increased the blood flow velocity. It was concluded that stress decreases blood flow in microvessels of gastric submucosa. The results revealed that glucocorticoids take part in normalization of blood flow of gastric microvessels during stress and this action can provide antiulcerogenic effect of corticosteroids which was shown by us previously.

[The effect of stress and corticosteroids on the rate of blood flow in the microvessels of the gastric muscular coat of rats]. / Vliianie stressa i kortikosteroidov na skorost' krovotoka v mikrososudakh myshechnoi obolochki zheludka krys.

In order to evaluate the influence of stress and corticosteroids on blood flow velocity in microvessels of muscular coat of the stomach we applied intravital microfilming by means of a dark-field contact epiobjective. The plasma filled "gap" in the continuous erythrocyte flow were used as the markers to measure linear flow velocity. In unstressed rats the velocity was equal to 1.76 +/- 0.07 mm/sec (182 microvessels, 3.7-8.7 mu in diameter). Stress (water immersion and restraint) led to a decrease of blood flow velocity in microvessels to more than double. A stress-induced decrease of blood flow velocity was greater in rats with insufficient corticosteroid production. The velocity of blood flow in these rats was lowered to 0.62 +/- 0.04 mm/sec. Replacement corticosterone therapy increased the blood flow velocity. It was concluded that stress decreases blood flow in microvessels of muscular coat of the stomach as well as in microvessels of mucosa. The results revealed that glycocorticoids take part in normalisation of blood flow of gastric microvessels during stress.

[The microcirculation in the cerebral cortex of rats at different stages of deep immersion hypothermia]. / Mikrotsirkuliatsiia v kore golovnogo mozga krys na raznykh stadiiakh glubokoi immersionnoi gipotermii.

A 25-30 degrees C hypothermia significantly increased the capillary blood flow in the rat cerebral cortex. A deeper hypothermia (17-15 degrees C) led to a stable decrease in the blood flow up to initial level. Breathing ceased at this stage, the cardiac activity being evident for 30-40 minutes after this. Deep hypothermia also led to a reversible aggregation phenomenon which seemed not to hinder the blood flow.

[The characteristics of the circadian motor activity of sturgeons and their hybrids studied by a motion picture-TV method]. / Izuchenie osobennostei sutochnoi dvigatel'noi aktivnosti osetrovykh ryb i ikh gibridov kinotelevizionnym metodom.

Technique of slow-motion shot was used for simultaneous automatic recording of behaviour of sturgeon species Acipenser nudiventris and its hybrid with white sturgeon, Huso huso. The hybrids and the individuals of the paternal species were placed in two separate aquaria under the conditions of constant light. Cinematographic recording was performed each hour throughout 3 days during 30 s per hour. Significant differences between two kinds of sturgeons were found in the locomotor activity, trajectory of swimming, the average value and circadian rhythm of the swimming speed. The hybrid individuals swim faster and display a high peak of night activity. This puts them close to the maternal species, white sturgeon, and gives evidence of the maternal inheritance of these traits.

[The circadian rhythm of the formation of stress stomach ulcers in rats]. / Tsirkadiannyi ritm obrazovaniia stressornykh iazv zheludka u krys.

Areas of stress-induced gastric ulceration vary parallels with changes of corticosterone levels. The ulceration was greater in the morning during low basal corticosterone level than in the evening during high one. Adrenalectomy ceased the circadian basal rhythm of corticosterone and the rhythm of stress-induced ulceration. The decrease of ulceration in the evening seems to indicate an increase of the body adaptability resulting from the circadian corticosterone increase.

[The open-field behavior of neuroticized rats]. / Povedenie v otkrytom pole nevrotizirovannykh krys.

A detailed study has been carried out of the behaviour in the open field of the lines of rats with different functional state of the nervous system after prolonged neurotization in dependence on the phase of circadian rhythm and terms after the end of the influence. Significant changes have been shown by the amplitude of circadian rhythms of emotionality and motor activity. It is established that the reaction of the rats lines to prolonged neuroticizing action depends on the phase of the circadian rhythm, the time after its termination and on genetically determined level of excitability of the nervous system.

[An analysis of the joint activities of primates in a situation of delayed spatial choice]. / Analiz sovmestnoi deiatel'nosti primatov v situatsii prostranstvennogo otsrochennogo vybora.

A leader-dominant baboon of a couple took practically all the food in the situation of spatial delayed choice. The subdominant baboon managed to get some food, too, using fast changes of behavioral tactics during the experimental session. The obvious negative state of the subdominant baboon resulted in a severe neurotic breakdown. Long delays in the experimental scheme enabled the subdominant to get up to 50% of the food reinforcement due to the dominant baboons mistakes. The role of changes in the tactics of the monkeys is discussed.

[A quantitative analysis of primate motor activity in a situation of delayed spatial choice. The individual behavioral reactions]. / Kolichestvennyi analiz dvigatel'noi aktivnosti primatov v situatsii prostranstvennogo otsrochennogo vybora. Individual'nye povedencheskie reaktsii.

Speed of movements in food getting responses of baboons, total time of the response, trajectories of the movements and other parameters revealed obvious changes during formation of conditioned activity. The data obtained suggest that many quantitative characteristics of the primate motor activity are specifically related to various aspects of complex behavioral responses.

[The microcirculatory changes in leukocytosis]. / Izmenenie mikrotsirkuliatsii pri leikotsitoze.

A moderate leucocytosis was found to decelerate the blood flow in the rat brain capillaries and to change the character of the blood flow. This seems to be due to a temporal obturation of the capillary lumen by one or several leucocytes.

[Changes in the blood flow velocity in the capillaries of the rat cerebral cortex in acute massive blood loss]. / Izmenenie skorosti krovotoka v kapilliarakh kory golovnogo mozga krys pri ostroi massivnoi krovopotere.

A statistically significant drop in the blood flow velocity in capillaries of the rat cerebral cortex occurred in 50-60% loss of the blood volume: from 1.32 +/- 0.1 mm/sec to 0.2-0.8 mm/sec even in 30-40% loss, resp. A more massive blood loss (50-60%) decreased the blood flow velocity with no subsequent restoration. Aggregates of elements were formed in the capillaries with subsequent hemostasis in this part of the vessel.