Reperfusion injury after critical intestinal ischemia and its correction with perfluorochemical emulsion "perftoran".

Aim: To investigate the anti-ischemic properties of perfluorochemical emulsion "perftoran" in mesenteric region.

Methods: Experiments were conducted on 146 nonlinear white male rats weighing 200-350 g. Partial critical intestinal ischemia was induced by thorough atraumatic strangulation of 5-6 cm jejunal loop with its mesentery for 90 min.

[Various forms of water in the rat myocardium and liver during blood loss and the early postresuscitation period].

Different forms of water content were studied in myocardium and liver of male rats at 2-h hypotension and during the early postreanimation period. The phenomenon of redistribution of free and bound water was found. Comparison of water balance during the postreanimation period in the myocardium and liver revealed that normalization of different forms of water occured in myocardium.

[Effect of perftoran on cerebral blood flow in the reperfusion period after global transient brain ischemia].

It was established, while modeling the global transient cerebral ischemia in experiments with 51 anesthetized nonlinear white rats (weight 300-330 g), that a preliminary administration of perftoran in the discussed pathology does not only improve the reperfusion process in the brain but also levels the deficits of crystalloid solutions used as blood substitutes (by the example of physiological solution). Therefore, the drug has a cytoprotective action on the vascular-system endothelium. A direct admixture of perftoran to the autoblood introduced after global transient cerebral ischemia improves essentially the reperfusion-period course in the brain versus the combination of physiological solution and autoblood.

[Cytogenetic changes of the bone marrow in massive blood loss and their correction with mexidol].

The citogenetic lesions were evaluated in the marrow erythroblasts of 45 anesthetized white nonlinear male rats, weight--200-300 g who were subjected to an acute blood loss with a 1-hour arterial hypotension (ABR = 40 mm Hg); the micronucleus tests was made use of. Two stages of the increase of polychromatophilic erythrocytes with micronuclei in the marrow of the animals, who underwent a massive blood loss, were registered: stage 1--an incomplete marrow ischemia with a subsequent arterial hypotension and with a reliably confirmed formation of cytogenetic lesions in the marrow polychromatophilic erythrocytes; stage 2--the reperfusion period contributed to a 1.7-fold increase of polychromatophilic erythrocytes with micronuclei versus the previous stage.

Water status and LPO in rat tissues during massive blood loss and irradiation with He-Ne laser.

We revealed a relationship between water balance and LPO in the myocardium, liver, and blood plasma during massive blood loss and irradiation with He-Ne laser. Low-intensity laser irradiation of the plasma inhibits LPO and normalizes water balance in rat tissues during massive blood loss.

[Effects of perftoran on experimental acute intestinal ischemia].

The studies were carried out on 76 albino noninbred male rats weighing 210-420 g. Ischemia of a jejunal segment was induced by applying a tourniquet to the base of a loop with the mesentery until the circulation fully stopped. Nonoxygenated perfluorane (an experimental group) or saline solution (a control group) was injected in a dose of 0.

[Laser radiation to correct disorders of blood albumin transport in severe mechanical trauma].

The paper provides evidence for that it is expedient to perform multi-stage intravascular low-intensity laser blood radiation in patients with severe mechanical trauma and massive blood loss in the early posttraumatic period. The use of laser radiation at a wavelength of 632.0 nm by inserting a disposable light guide (its end power was 1.

[Acute and massive hemorrhage: mechanisms of compensation and damage].

To evaluate the body's compensatory reserves, experiments were made on anesthetized (with heparine) mongrel dogs of both sexes weighing 8-25 kg. The experiments have indicated that early monitoring of physiological parameters (external respiration, cardiovascular performance, hemostasis, red blood cell morphometry) in the first 5-10 minutes of acute massive hemorrhage is of high informative value. The generalization of vasoconstriction resulting in higher overall blood volume, the maintenance of venous return, tachypnea, active spontaneous hemodilution, and increased heart rate are the leading mechanisms of perfusion pressure maintenance in early acute hemorrhage.

[Effect of laser exposure on hemostatic parameters in the preagonal and post-resuscitation period].

Effects of intravascular low-intensive laser exposure of the blood on the hemostasis during acute blood loss and the early postresuscitation period after 4-min clinical death were studied on narcotized dogs (8-17 kg) of both sexes with different initial levels of heparin. During the preagonal period laser exposure caused hypercoagulation in animals with initial heparin content below 60 micrograms/ml. This acceleration of blood clotting prevented a drop in the activity of antithrombin III and hypercoagulation by the third hour of postresuscitation period.

[Neurobiological mechanisms of massive blood loss].

Molecular mechanisms of neuronal death (apoptosis and necrobiosis) in massive blood loss and at various stages of the postreanimation period are investigated from the neurobiological viewpoint. The activities of these processes are quantitatively evaluated and their specific features in incomplete cerebral ischemia, reperfusion (reanimation), and during the postischemic (postreanimation) period are analyzed.

Morphologic changes of red blood cells during hemorrhagic shock replicate changes of aging.

Blood loss leads to the reduction in vitality of red blood cells (RBCs). However, the changes in morphology at different stages of hemorrhagic shock have not been studied. Thus, the aim of this study was to identify and quantitate the sequence of morphological changes in RBCs during hemorrhage.

[The biogenic amine content of rat tissues in the postresuscitation period following hemorrhagic shock and the effect of the preparation semax].

LPO products were measured in plasma and biogenic amines (serotonin, adrenalin, noradrenalin) in tissues of rats in different periods after hemorrhagic shock provoked by taking blood and maintenance of arterial pressure at the level of 40 mm Hg for 1 hour. Resuscitation was conducted by administration of autoblood. It was found that splenic serotonin levels decreased on experiment day 7 and went up on day 28.

[Hemocoagulation while dying of blood loss and restoration to life after clinical death].

Hemostatic system function was studied in dogs dying of acute blood loss and restoring to life after 4-min clinical death. Phasic changes in hemostatic system of two and three types occurred in the blood loss and reanimation, respectively. Dogs with favorable postresuscitation period exhibited hypercoagulation when dying, hypocoagulation 1 hour after reanimation and normal coagulation 3-6 hours after clinical death.

[DNA-endonucleolysis in cell nuclei of brain and liver in patients dying from hemorrhage and after resuscitation: general patterns and differences].

Specific features of Ca2+, Mg2+ dependent DNA endonucleolysis in the nuclei of the cerebral cortex, hypothalamus and liver were investigated in mongrel anesthetized male and female dogs. The endonucleolysis was studied in different periods of long-term arterial hypotension and in postresuscitation period, with strain pUC 19 plasmids as substrate for determination of nuclear endonuclease activity. It was established that nuclear DNA-endonucleases coupled with chromatin activated earlier in brain cortical and hepatic neurons than in the hypothalamus.

[Low-energy laser irradiation of blood as a method of prevention of blood circulation decompensation in hemorrhagic shock].

Effect of low-intensity laser exposure of the blood on the central hemodynamics, oxygen transporting function of the blood, oxygen balance of the organism, and surface configuration of erythrocyte membranes was studied in dogs exposed to 2-h arterial hypotension (arterial pressure 40 mm Hg). Blood exposure was started from the tenth min of hypotension and went on for 45 min (group 2) or 120 min (group 3); group 1 was control. The best results were attained after 45-min laser exposure.

[Effect of verapamil on the activity of Ca2+-, Mg2+-dependent endonucleases in hypothalamic cell nuclei in long-term hypovolemic shock].

Experiments on anesthetized non-inbred 8-17 kg b.w.dogs have demonstrated that cerebral ischemia consequent to 4-hour hypovolemic shock activates Ca(2+)-, Mg(2+)-dependent endonucleases in cell nuclei of the hypothalamus.

[The effect of low-intensity laser radiation on the parameters of the blood anticoagulation system in the early postresuscitation period].

The effect of low-intensive laser exposure at a wavelength of 634 nm and power 1 mWt at the tip of the light-guide on the blood anticoagulative system was studied in mongrel narcotized dogs of both sexes weighing 8 to 16 kg during the postresuscitation period after 4-min clinical death from massive blood loss. The anticoagulative system in the blood plasma was depleted during the reanimation period (the activities of plasmin and fibrinogen-heparin complexes and the level of heparin dropped). Intravascular laser exposure of the blood (for 30 min during blood loss after drop of the mean arterial pressure to 40 mm Hg and at the beginning of the second hour of the postreanimation period) boosted the activities of plasmin and fibrinogen-heparin complexes but failed to increase the level of heparin in the postreanimation period.

[The neurochemical, molecular and ultrastructural mechanisms of the formation of latent postresuscitation encephalopathy].

The content of total RNA and DNA, activity of Ca2+, Mg(2+)-dependent DNA endonuclease, and ultrastructural changes in nerve tissue cells were examined in the brain cortex of narcotized dogs 1 to 3 months after a 4-hour hemorrhagic shock (arterial pressure 40 mm Hg). A new variant of reconstruction of cell membranes and organelles formed by them was revealed, developing in the brain neurons in the course of adaptation during the first-third months of the postshock period. Evidently, the molecular base of development of an atypical variant of cell structure rearrangement in the remote period after shock is the internucleosomal fragmentation of a part of the DNA of nerve cells resultant from DNA endonucleolysis and subsequent information disintegration of a cell as a system.

[Changes in the functional status of the left-ventricular myocardium during dying and in the early postresuscitation period].

Experiments on dogs have shown that left-ventricular contractility reduces and the processes of contraction and relaxation are discoordinated during the first minutes of dying from acute blood loss with the mean arterial pressure of 40 mm Hg. During the postreanimation period following a ten-min clinical death spontaneous respiration is resumed late (after 15.1 +/- 3.

[Changes in the oxygen balance of the body in the acute period of hemorrhagic shock and after resuscitation under the effect of intravascular helium-neon laser irradiation of the blood].

The effect of intravascular laser irradiation of the blood (ILIB) on the oxygen budget of the body and blood acid-base balance in the acute period of hemorrhagic shock and after resuscitation was studied in experiments on dogs. Duration of hypotension was 2 h. Laser therapy was started from the 5th-8th min of hypotension and lasted for 45 min; it was performed with a He-Ne laser (ALOK-1, 1 mWt power at the tip of the light guide, wavelength 633 nm) introduced in the right jugular vein.

[Significance of DNA endonucleases in the pathogenesis of ischemic lesion of the brain during massive hemorrhage].

Experiments on dogs exposed to hemorrhagic shock demonstrated a direct relationship between the duration of arterial hypertension and activities of Ca(2+)-Mg(2+)-dependent DNA-endonucleases in the cellular nuclei of the cerebral cortex. Appreciable differences in the kinetics of accumulation of acid-soluble products of DNA chromatin in the cellular nuclei of the cerebral cortex were detected: chromatin DNA degradation was the most rapid in the nervous tissue of dogs exposed to 6 h hemorrhagic shock. Verapamil, a Ca blocker, injected to animals 30 min before massive hemorrhage in a dose of 0.

[Molecular and cellular mechanisms of ischemic damage of the brain in hemorrhagic shock].

General lightening of caryoplasma, the appearance of destructive areas in which electron-optic density was undetectable, ruptures in chromatin chains, changes in the nature of structural organization of euchromatic areas at the expense of density redistribution have been found in the nuclei of brain cortex oligodendrogliocytes and astrocytes by electron microscopy of caryoplasma of the nuclei from light neurons during experiments on anesthetized adult mongrel dogs weighing 9 to 26 kg recovered after a 4-hour hemorrhagic shock (BP 40 mm Hg). The nuclei of dark neurons and oligodendrogliocytes had matrix structure similar to control. The nuclei of astrocytes had marked matrix lightening with the formation of large zones in which electron-optic density was undetectable.