Activity in the hypothalamo-hypophyseal-adrenocortical system on experimental induction of chronic fatigue syndrome.

Changes in the activity of the hypothalamo-hypophyseal-adrenocortical system (HHACS) were studied in an experimental model of chronic fatigue syndrome induced by i.p. administration of synthetic doublestranded RNA (polyriboinosinic:polyribocytidylic acid, Poly I:C) at a dose of 3 mg/kg.

Characteristics of cellular proliferation in the developing human retina.

The expression of proliferation-associated proteins Ki67 and PCNA was studied in the retinal rudiments of human embryos at 5-8 weeks of development; studies also addressed the numbers of nucleoli in the nuclei of neuroepithelial cells (with consideration of their distances to the apical surface) and DNA-synthesizing cells after transient (20 min) in vitro incubation in serum-free medium containing BrdU. The retinal rudiment of embryos at five weeks of development had neuroepithelium of the typical structure. BrdU-positive nuclei and nuclei with small numbers of nucleoli were located in the basal part of the ventricular zone.

Status of the "protein kinase CK2-HMG14" system in age-related amnesia in rats.

The experiments described here demonstrate that disruption of the phosphorylation of transcription factors of the HMG cAMP/Ca-independent protein kinase CK2 class may be the cause of decreased gene expression in age-related cognitive deficits. Amnesia for a conditioned passive avoidance reaction (CPAR) in aged rats (24 months old) was accompanied by decreases in the synthesis of synaptosomal proteins and transcription in nuclei isolated from cortical, hippocampal, and striatal neurons. There was a decrease in chromatin protein kinase CK2 activity and a significant decrease in the phosphorylation of HMG14 by protein kinase CK2.

Antigen-induced activation of hypothalamic cells (assessed by expression of the c-fos gene).

The aim of the present work was to study the activation of the expression of the c-fos gene (by in situ hybridization) in cells from rat (Sprague Dawley) hypothalamic structures 0.5, 2, 6, and 16 h after i.v.

Lateralization of brain trauma in female Wistar rats determines the immune and neurological status of offspring.

Unilateral trauma to the sensorimotor cortex in ambidextrous maternal female rats decreased the resistance of their offspring, as indicated by a reduction in the functional activity of natural killer cells. Offspring rats showed T-cell immunodeficiency regardless of the lateralization of the trauma in their mothers; this was more severe after right-sided trauma (both mature and immature T-lymphocytes were affected). The EMG pattern of evoked responses in offspring rats changed according to the lesions evoked by unilateral trauma in their mothers (in the muscles responsible for postural asymmetry).

The effect of L-tryptophan on conditioned reflex learning and behavior in rats with experimental pathology of the thyroid gland.

The effects of L-tryptophan on conditioned reflex learning and behavior were studied in male rats with deficient and excess thyroid hormones levels. The learning process was studied using a model consisting of a conditioned active avoidance response; animal behavior was assessed in an open field test. These studies showed that in conditions of thyroid hormone deficiency.

The role of neutral sphingomyelinase in interleukin-1beta signal transduction in mouse cerebral cortex cells.

The cytokine interleukin-1 (IL-1) is an important mediator of neuroimmune interactions, though it has not been established precisely how the IL-lbeta signal is transmitted in nerve cells. This study demonstrates the involvement of the sphingomyelin cascade in IL-1beta signal transduction in the P2 membrane fraction of the mouse cerebral cortex. The key role of the membrane enzyme neutral sphingomyelinase in initiating the sphingomyelin signal transduction pathway for this cytokine is supported.

The role of interleukin-1 in stress-induced changes in immune system function.

The cellular-molecular mechanisms of changes in immune system function were studied, including the production of lymphocyte activating factor (LAF) and interleukin-1 (IL-1). the effects of IL-1 on target cells, and subsequent cytokine signal transduction via the sphingomyelin pathway, in different types of stress. These experiments showed that stress of different durations and intensities induced the formation of lymphocyte activating factors by peritoneal macrophages and increased IL-la levels in mouse blood.

The role of D1-dependent dopaminergic mechanisms of the frontal cortex in delayed responding in rats.

The effects of local microinjections of D1-selective dopaminergic agents into the medial wall of the frontal cortex of rats on short-term memory processes were studied, along with the effects of proactive interference in immediate and delayed spatial choice tasks in a Y maze. Microinjections of the D1 receptor antagonist SCH23390 (1 nmol) disturbed performance of both immediate and delayed choice tasks. while administration of the D1 receptor agonist SKF38393 (1 nmol) had no effect on immediate choice and improved delayed performance.

Analysis of the dynamics of interneuronal functional connections during conditioned reflex activity.

The dynamics of interneuronal functional connections were studied in the prefrontal cortex of dogs performing a task consisting of unforeseen remodeling of movement conditioned reflexes. An original method was used to find and classify the temporal patterns of linked spikes coming from several simultaneously recorded neurons. This procedure showed that in 33 pairs of neurons (87% of the total number of pairs showing interneuronal functional connections), parts of the conditioned reflex program were associated with behaviorally significant changes in the functional relationship between the neurons.

The effects of peripheral endocrine hormone deficiencies on the processes of behavior, learning, and memory.

The effects of thyroid and adrenal cortex hormone and sex hormone deficiencies on the ability to learn, store memory traces, and behave were compared in male rats. These studies showed that removal of peripheral endocrine glands led to disruption of the learning process and the ability to reproduce learned information and also produced alterations in behavior. Analysis of the results showed that corticosteroid hormones are directly involved in the processes of learning and behavior.

Immunohistochemical studies of the structural bases of inhibition in the central cerebellar nuclei in mice.

The distribution of glutamate decarboxylase-immunoreactive structures in the central nuclei of the cerebellum, its first afferent component, was studied at the light and electron microscope levels. Axosomatic, axodendritic, and axospinous synapses were detected, in which the presynaptic parts contained glutamate decarboxylase (GDC); this enzyme is involved in GABA synthesis. Additionally, these investigations revealed axoaxonal synapses in which both poles were GDC-reactive.

The effects of the hormones of peripheral endocrine glands on the processes of behavior, learning, and memory.

The effects of systemic administration of thyroid, adrenal cortex, and sex hormones on learning ability, memory trace retention, and behavior were compared in male rats. These studies showed that thyroid, corticosteroid, and sex hormones had no effect on passive learning. Excess quantities of sex hormones disrupted active learning and subsequent reproduction of received information; an excess of thyroid hormone improved the acquisition and retention of the active avoidance habit.

Comparative characteristics of learning and behavior processes in conditions of elevated sex hormone levels.

The effects of elevated levels of sex hormones resulting from systemic administration of hormone preparations on the abilities to learn and retain memory traces and on behavior were studied in rats of both sexes. Experiments were performed using models of conditioned active and passive avoidance reflexes and in the "open" field test. Increases in testosterone and estradiol levels had no effect on passive learning.

Involvement of the genetic apparatus in memory formation mechanisms: the role of the neuronal calcium-regulatory system in rats.

Stimulators of long-term memory (ethylnorantiphein and its analogs M1 and M2) were used to study the dynamics of several components of the neuronal calcium-regulatory system in the rat cortex and hippocampus. There were no changes in the activity of the Mg, Ca-ATPase transporter and actomyosin-like Ca-ATPase in synaptosomes 5, 15, 60, and 180 min after dosage with these agents. On exposure to ethylnorantiphein, M1, and M2, activation of RNA transcription at 60 min was accompanied by notable increases in chromatin Ca-ATPase activity, along with an increase in the synthesis of synaptosomal proteins at 180 min, with an increase in synaptic membrane protein kinase C activity.