Effect of embryonic brain tissue transplantation on structural changes in the rat brain after craniocerebral trauma

The effect of homotopic allotransplantation of embryonic cerebral cortex tissue on structural changes in the brain were studied on rats who had suffered a severe craniocerebral trauma (CCT) and subsequent traumatonesis of an injured region. Using Nissl and Golgi-Cox techniques, we showed that the presence of a viable graft in the cavity created by the traumatonesis procedure prevented formation of coarse gliofibrous expansions and extensive dead zones within the perifocal region of the injury locus. Transplantation performed immediately after the CCT and traumatonesis appeared to be most effective. In this case, the graft growth was more intensive and it was better integrated into the recipient's brain; branching of neurons in the graft was more abundant, and their dendrites were densely covered with spines. Thus, the use of early transplantation prevents the development of destructive and dystrophic changes evoked by severe CCT and can be regarded as a promising direction in neurosurgical practice.Neirofiziologiya/Neurophysiology, Vol. 27, No. 5/6, pp. 350–360, September–December, 1995.     

Bacterial meningitis after craniocerebral trauma in the community

Craniocerebral trauma is one of major risk factors for development of meningitis. We reviewed 30 cases of bacterial meningitis occurring in community after craniocerebral trauma. Alcohol abuse was significant risk factor occurring in trauma patients with meningitis present in 50% in our cohort (p=0.0001). The most common pathogen in posttraumatic meningitis was Str. pneumoniae (90% vs. 33.8%, p=0.0001). However mortality was very low, only 5% probably because of early diagnosis and treatment of patients at risk for bacterial meningitis but neurologic sequellea were significantly more common (p=0.00001) in patients after craniocerebral trauma.     

Effect of a varying corticosteroid allowance on the cAMP content of limbic system structures of the rat brain

A study was made of the effect of adrenalectomy and substitution therapy in the absence of adrenals on the cAMP content in the hypothalamus, hippocamp and striate body of the rat brain. It was shown that in sham adrenalectomized animals, the concentration of cAMP in the brain structures under study did not differ from the characteristics recorded in the control group. Adrenalectomy in rats was followed by a significant reduction of the nucleotide in all the structures, namely in the hypothalamus by 89.5%, and in the hippocamp and striate body by 30.3 and 30.5%, respectively. Application of substitution therapy (5 mg hydrocortisone per 100 mg body mass) prevented the decreased content of cAMP seen in the adrenalectomized rats, with its magnitude being within the limits recorded in the intact animals. Doca was little effective in this aspect.     

The cAMP content and cAMP-dependent protein kinase activity in the brain of rabbits in the dynamics of moderate craniocerebral trauma

An intracellular concentration of cAMP is a factor to define activity of cAMP-dependent protein kinases. Enzyme activity changes in cytosol and microsomal fractions from investigated brain's regions. Two-phase character of posttraumatic changes of A-kinases activity is shown. Linear dependence for microsomal fractions obtained from brain's hemispheres is observed between A-kinases activity and calculated equilibrium cAMP concentration in different time after experimental cranial trauma.     

Effect of infusing the branched-chain amino acids on concentrations of amino acids in plasma and brain and on brain catecholamines after total hepatectomy in the rat

In totally hepatectomized rats supported by infusion of glucose, the concentrations of many amino acids in plasma and brain rose progressively over time, while the brain levels of norepinephrine decreased. Infusion of a solution containing glucose, leucine, isoleucine, and valine after hepatectomy greatly reduced the accumulation of other essential amino acids in plasma and brain. However, the decrease in brain norepinephrine content was not significantly affected by this infusion, suggesting that high brain concentrations of monoamine precursor amino acids are not the primary cause of norepinephrine depletion after hepatectomy.     

Effect of transplantation of embryonic neural tissue on the dynamics of brain edema following experimental craniocerebral trauma

The effect of transplantation of embryonic neural tissue (ENT) on the dynamics of brain edema following heavy craniocerebral trauma (CCT) made to the left parietotemporal area was studied in rats. The brain tissue impedance was measured in the damaged and contralateral hemispheres 1 to 30 days after the trauma in the animals of three groups: (i) without any procedures after the CCT, (ii) with surgical treatment of the damaged brain area, and (iii) with transplantation of 1–2 mm³ sensorimotor cortex fragments from 18-day-old rats grafted into the cavity created by this treatment. At the first day after CCT, the impedance in the damaged hemisphere decreased by 30–37%, while the impedance in the contralateral hemisphere decreased approximately by 20%, compared with the control, which was evidence of the development of intensive generalized edema. In the group of animals with the ENT transplantation, the edema involuted noticeably faster than in the other two groups: the mean impedance value reached 97.9% of the control value (before the damage) already by the 7th post-traumatic day. Complete recovery of the impedance by the 30th day was observed only in the animals with transplantation. The adequacy of an impedancemetric technique for investigation of the dynamics of water-electrolyte re-distribution in the brain tissue, and the mechanisms underlying corrective effect of ENT transplantation on the edema dynamics in the post-traumatic period are discussed.     

Effect of reserpine administered during infancy on brain catecholamines and adult behaviour in the rat

Reserpine (0.1 mg/kg/day) was administered to rats from 11 through 30 days of age. During and after administration of reserpine, concentrations of catecholamines, epinephrine and norepinephrine, in the brain were estimated. Levels of catecholamines were about 30 per cent of normal during the period of reserpine administration. Approximately 3 weeks were required for these levels to return to normal. When animals were 95-100 days of age, they were deprived of food and were trained to press a bar for food. When the rate of responding became stable, the animals were subjected to three successive extinctions at daily intervals and the increase in response rate after the onset of each extinction was determined. This extinction-induced increase in response rate was greater for previously reserpinized animals than controls during the second and third extinctions, but not the first. These findings are interpreted as a decreased ability of the animals, reserpinized during infancy, to learn to respond discriminatively during non-reinforcement (extinction). Thus, an effect of reserpine administration during infancy on a type of behaviour in the adult has been demonstrated. This occurs after the catecholamine-depleting effect of the reserpine has been fully dissipated.     

Effect of hypokinesia on the ultrastructure of emotion-controlling structures in the rat brain

Hypokinesia lasting 40 and 90 days causes a number of ultramicroscopic reorganizations in neurons, synapses and glial elements of the singular cortex and the central amygdaloid nucleus. The longer the time of hypokinesia, the more numerous and variable the reorganizations become. For the amygdaloid body presence of neurons with various degree of chromatolysis, reactive and destructive changes of organells, agglutination and reduction in number of the synaptic vesicles, increasing number of synapses, possessing certain features of low functional activity are most specific. For the singular cortes are peculiar convolution of nuclear and cellular membranes, synaptic contact, increasing intercellular spaces, as well as changes in the structure of some axo-spine synapses, the spine apparatus including.     

Regional distribution of catecholamines in rat brain after L-3-O-methyldopa and L-dopa

The distribution of labelled dopamine (DA) and noradrenaline (NA) in the various brain regions of the rat was similar after administration of L-¹⁴C-3-0-methyldopa (OMD) or L-¹⁴C-dopa, DA showing the greatest accumulation in the striatum and NA in the hypothalamus. The concentration of catecholamines 2 hours after OMD amounted to 2–15 % of those found after L-dopa. In the whole brain, the cerebral catecholamines formed from dopa decreased more rapidly than those originating from OMD. In conclusion, OMD is a precursor of cerebral catecholamines; however, it is less effective than dopa.     

Correction of immunity disorder developing after craniocerebral trauma

The article presents some data concerning influence of humoral factor received from blood serum of injured animals on humoral and cell immune response of animals. The results show that administration of humoral factor prevents stress-induced devastation of thymus, improves humoral immune response to antigen test (sheep erythrocytes) and restores hypersensitivity of decelerated type (HDT) reactions. Immune stimulating effects are observed both right after cranial trauma and some time later -- 5-7 days after the injury.     

Effect of electroconvulsive shock on the content of thyrotropin-releasing hormone in rat brain

Five grand-mal seizures were electrically induced in rats on alternate days. Forty-eight hours following the last seizure, TRH was quantitated in extracts of anterior cortex, hippocampus, striatum, thalamus plus midbrain, and hypothalamus. When compared to sham treated controls, TRH was found to be elevated 5-fold in the hippocampus and 2-fold in the striatum with no changes observed in the remaining regions. Since the time chosen for analysis excludes acute post-ictal effects, these results draw attention to a prolonged alteration of TRH levels in specific brain regions in an animal model of electroconvulsive treatment.     

The content of NCAM in rat brain structures in conditioned passive avoidance reactions

The content of neural cell adhesion molecule, NCAM, was measured in the brain of rats that acquired a habit of passive defensive behavior, and rats that lost or preserved this habit after electroshock. A significant increase in the NCAM concentration in the striatum was observed in amnesiated animals. These results may be evidence of plastic rearrangements of neuronal networks, responsible for learning and memory, and direct involvement of NCAM in these modifications.     

Effect of copper deficiency on the concentrations of catecholamines and related enzyme activities in the rat brain.

Immature rats were made copper deficient by feeding them a low (< 1 p. p. m.) copper diet. During the gestation and lactation periods their dams consumed the same diet. Controls received a dietary supplement of 10 p. p. m. copper. At approx 7 weeks of age, the deficient animals exhibited signs of neurological dysfunction and gross lesions of the brain. Cytochrome oxidase activity and copper content of the liver and brain were used as criteria of copper status and confirmed the existence of severe deficiency. The whole brains minus cerebella of the deficient animals contained approx 30% less dopamine and norepinephrine than those of the controls. The tyrosine hydroxylase activity was depressed more than 25% in the copper deficient brains while the superoxide dismutase activity was lowered more than 35%. There was a high correlation between the chief criterion of copper status, liver cytochrome oxidase activity, and the brain concentrations of dopamine, norepinephrine and tyrosine hydroxylase activity. The decrease in activity of tyrosine hydroxylase was sufficient to account for the lowered concentrations of the catecholamines.     

Dynamics of morphofunctional state of the epiphysis after craniocerebral trauma in humans

Histological examination of the epiphyses of 12 persons who perished because of craniocerebral trauma (CCT) showed that even in the first hours after CCT clear manifestations of considerable morphofunctional transformation of epiphyseal cellular elements towards intensification of indoleamine production become obvious. In the cases of death on the 11th–12th post-traumatic day, we observed complete morphofunctional exhaustion of the epiphysis: the cell elements with typical features of pinealocytes practically disappeared.