Zh Vyssh Nerv Deiat Im I P Pavlova
December 2005
Male white rats divided in three groups on the basis of their behavior in the elevated plus-maze were subjected to 10-min cardiac arrest. Analysis of the results of their subsequent food and active avoidance conditioning revealed the effects of the following factors: (1) a factor of initial typological features of the higher nervous activity, (2) a factor of general brain mechanisms of postresuscitation, and (3) a factor of postresuscitation features in rats with different behaviors, which represented changes in different mechanisms of conditioned reflex performance in these animals.
View Article and Find Full Text PDFThe elevated cross-shaped labyrinth test carried out on highly, moderately, and low active experimental animals revealed significant differences in the baseline density and composition of neuroglial populations of numerous formations of the brain, as well as in the early structural and functional sequels of experienced clinical death. The most pronounced postresuscitation abnormal changes were observed in highly active animals and the least marked ones were seen in moderately active animals.
View Article and Find Full Text PDFThe effect of perfluorane on survival and restorative process in the brain were studied in rats subjected to 12-min arrest of systemic circulation. Perfluorane in a single dose of 5-10 ml/kg was injected intraperitoneally 30 min after the beginning of reanimation. The drug did not affect the postreanimation death of animals and time course of neurologic deficiency disappearance.
View Article and Find Full Text PDFZh Vyssh Nerv Deiat Im I P Pavlova
October 1999
Male Wistar rats with different types of behavior in "emotional resonance" test ("active" and "passive") were studied one week after the global ischemia induced by cardiac arrest. Recovery of some physiological functions as well as free-radical-mediated processes and NO-synthase activity were studied in cerebral structures and blood serum. The "open-field" behavior normalized more rapidly in the "active" rats than in the "passive" ones, though the time course of the neurologic deficit compensation did not differ in these groups.
View Article and Find Full Text PDFCirculation in white rat males was stopped for 10 minutes by ligation of the intrathoracic vascular bundle of the heart. Proxipin in a dose 10 or 20 mg/kg was injected i.p.
View Article and Find Full Text PDFEfficacy of prolonged (days 10-60 after resuscitation) regular activation of behavior by labyrinth training of 4-staged food search conditioned reflex is studied in rats subjected to 15-min circulation arrest. This training affected the function of the central nervous system, which manifested by decreased anxiety and a higher activity in the open field test. This functional exercise prevented fall-out of neurons in the fifth layer of hemispheres, of cerebellar Purkinje's cells, and of pyramidal neurons in hippocampal sector CA1.
View Article and Find Full Text PDFFree radical-mediated processes and NO-synthase activity were studied in cerebral structures and blood serum of male Wistar rats with different types of behavior in emotional resonance test one hour after global ischemia induced by cardiac arrest. Oxidative stress accompanied by loss in NO-synthase activity was revealed in cerebral cortex after the ischemia. The oxidative stress was also evident in cerebellum and to a lesser extent in hippocampus.
View Article and Find Full Text PDFThe effect of oral succinic acid was studied in rats exposed to 10-min heart arrest followed by resuscitation. The drug was administered for 5 days in a dose of 30 mg/kg starting from day 3 up to day 7 after resuscitation. Succinic acid was found to normalize the orientation and exploration behavior of rats in the "open field" test, decreased the intensity of response to stress (electric shock), and normalized the radical formation in the brain tissue and blood serum, thus reducing the morphological changes in the brain.
View Article and Find Full Text PDFExperiments with rats resuscitated after clinical death compatible with a complete and relatively rapid recovery of the neurologic status proved that prolonged (a follow-up of up to 9 months) and varying in time changes in a number of parameters of the higher nervous activity and behaviour occur in the postresuscitation period. Postresuscitation changes in behaviour correlate with the data on the degenerative changes in a number of cerebral structures of resuscitated rats progressing over 9 to 12 months. The available data of functional and morphological studies indicate the possibility of development of latent slowly progressing degenerative changes in the CNS of the organisms surviving clinical death and resuscitation.
View Article and Find Full Text PDFTherapeutic effect of sodium succinate on various functional, biochemical, and morphological parameters of CNS repair was studied in experiments on rats exposed to 10-min circulation arrest. The first series of experiments was devoted to studies of the effects of the drug, injected intraperitoneally directly after recovery of effective cardiac activity and during the subsequent 5 days in doses 20, 100, and 200 mg/kg, on the survival and recovery of the external neurologic status. The dose of 20 mg/kg proved to be the most effective.
View Article and Find Full Text PDFThe experiments have indicated that the first week of postresuscitation is marked by enhanced goal-investigating behaviour in the open field, by the accelerated learning of an operant reflex, and by decreased anxiety in the conflict situation test in male rats undergone a 10-min arrest of systemic circulation. There was a depressive behavior in the open field following 6-8 weeks with the normalization of operant reflex learning and the level of anxiety in the conflict test situation. Gidazepam (3 mg/kg, i.
View Article and Find Full Text PDFRats recovered after a 10-min circulation arrest, were examined in the early postresuscitation period (within 10-12 days after resuscitation) in an open field (OF) test and during elaboration and reproduction of passive avoidance conditioned reflex (PACR); morphometric analysis of sensorimotor brain cortex was performed on days 4, 7, 14, and 30 after resuscitation. It has been shown that directly after compensation of external neurological deficit which took place in the majority of animals within 3 days the process of adaptation to new situation (OF test) in resuscitated rats, unlike the intact ones, was associated with high motor activity and not with the elaboration of stable correlations between various behavioral acts. At the same time disorders in learning and memory have been observed in PACR test.
View Article and Find Full Text PDFCardiac output distribution and oxygen supply in the period starting from 15 min after resuscitation to 7 h were studied in 23 dogs exposed to 10 min clinical death caused by blood loss. The ratio of supra- to subdiaphragmatic bloodstream was virtually unchanged. Redistribution of the flow in favor of hind limb muscles was observed in the subdiaphragmatic region only between the 15th and 30th minutes.
View Article and Find Full Text PDFIn 43 experiments performed on narcotized dogs after 10 min clinical death induced by exsanguination, the peculiarities of postresuscitation changes in the blood circulation associated with the initial hemodynamic status, the rate of the blood loss replacements after restoration of cardiac activity, and the use of infusion therapy by albosorb (specifically processed albumin) were studied. The effect of the initial level of stroke index (SI) on the pronouncement of postresuscitation derangements in the central hemodynamics (CHD) and on the resuscitation outcome was determined. With the initial value of SI being mean, the maintenance of a moderate blood deficit (10 to 15 ml/kg) within the first hour of restoration was accompanied by an improvement in the survival rate of the animals as compared with a rapid and complete replacement of the blood.
View Article and Find Full Text PDFZh Vopr Neirokhir Im N N Burdenko
December 1987
The theoretical aspects of employing the infusion methods of examination of CSF time course and viscoresilient properties of the cerebrospinal system (CSS) are discussed. The general formula of changes in the time of intracranial pressure (TIP) after a load is given. Dog experiments showed this formula to reflect sufficiently exactly the behavior of the CSS in a TIP range of 24 to 40 cm H2O.
View Article and Find Full Text PDFFiziol Zh SSSR Im I M Sechenova
June 1981
On the basis of Fick's principle, concept of the tissue blood flow heterogeneity and H2 concentration changes in arterial blood after short-term hydrogen inhalation, a method of calculating some blood flow indices in the limbs by H2 content desaturation changes in venous blood was developed. The suggested method allows to calculate the mean regional flow rate, its compartmentation, and blood flow/tissue volume ratio for the measured components of the regional blood flow. In the limb tissue of anesthetized dogs, two components of the blood flow with the rates 0.
View Article and Find Full Text PDFThe role played by the amygdaloid nucleus, caudate nucleus, thalamus and brain cortex in propagation throughout the brain of generalized limbic alpha-like activity recorded on the EEG in the early postresuscitation period was studied in experiments on dogs resuscitated after a 13-15-minute circulatory arrest. Destruction or pharmacological inhibition of both amygdaloid nuclei resulted in disappearance of alpha-like activity from all the test structures. Coherent analysis showed that the caudate nucleus and thalamus, in particular, take an active part in propagation of alpha-like waves of biopotentials from the amygdaloid nucleus to other brain structures.
View Article and Find Full Text PDFIt was shown in experiments on 25 dogs that the generalized a-like limbic activity is recorded on ECoG in the post-resuscitation period after 12-minute cardiac arrest largely in the cases of forced spontaneous breathing. The use of large tidal volumes of artificial lung ventilation during resuscitation significantly diminished frequency of the appearance on ECcG of the activity in question because of hypccapnia and resultant suppression of the respiratory centre. The forced work of the respiratory centre is conducive to the development of this activity by irradiating the excitaticn to the higher brain structures.
View Article and Find Full Text PDFPrevious experiments on dogs showed that in several cases, along with the development of hypoxia, polymorphous delta-waves changed into synchronous oscillations, also of delta range, the so-called standard slow complexes (SSC). The new experimental data showed discharges of neuronal pool during SSC to be present in the caudate nucleus, lateral and medial thalamus, hypothalamus, hypocampus, n. amygdale, and mesencephalic reticular formation.
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