Ultrastructural Changes in the Penumbra of the Local Cerebral Infarction in Rats.

We studied changes in the ultrastructure of synapses and myelin nerve fibers that develop in the penumbra in 4 and 12 h and 2 and 4 days after modeling infarction in the frontoparietal cortex in rats. Ischemic stroke was induced by injection of a photosensitive dye into their bloodstream followed by illumination of the brain surface with a halogen lamp. Visible ultrastructural changes were observed in the penumbra zone, namely in the axodendritic and axospinous synapses; they consisted in polymorphism and disorganization of synaptic vesicles, mitochondrial swelling, swelling and vacuolization of the postsynaptic fragments of dendrites, and shortening and osmiophilia of the active zone.

RADON HORMESIS IN EPILEPTIC PATHOGENESIS AND PREDICTORS OF OXIDATIVE STRESS.

Numerous experimental and clinical studies have shown that oxidative stress (OS) plays an important role in the development of epilepsy. The epileptic seizures themselves are caused by OS and, under conditions of a hypermetabolic state, cause an intensive production of reactive oxygen species (ROS) in the brain. The reason for this is called a change in the energy balance in the brain.

Some Aspects of Role of Nitric Oxide in the Mechanisms of Hypertension (Experimental Study).

Background: Modulation of endothelial function is a therapeutic option to reduce some of the significant complications of hypertension. However, the relationship between endothelial dysfunction reduced nitric oxide (NO) production, and the development of hypertension is not fully understood. To establish a potential pathogenetic link between impaired NO synthesis and hypertension, we investigated the results of competitive interaction of the substrate of NO synthase, L-arginine, and its analog, an non-selective inhibitor of NO synthase, N-nitro-methyl ether-L-arginine (L-NAME), in experimental rats.

CHANGES IN ARTERIOLE REACTIVITY TO NORADRENALINE UNDER CONDITIONS OF HYPERHOMOCYSTEINEMIA.

The aim of the research was the experimental study of one of the possible mechanisms performing contractile activity of arterioles in hyperhomocysteinemic animals. Moderate hyperhomocysteinemia was induced in male rats (120-160 g., n=12) by adding L-methionine to the drinking water during 4 weeks.

EFFECTS OF HIGH AND LOW DOSES OF ETHANOL, GIVEN TO RATS DURING THE PROCESS OF PREGNANCY, ON THE BEHAVIOR AND THE BLOOD RHEOLOGICAL PROPERTIES OF THEIR OFFSPRINGS.

In our experiments it has been established that during pregnancy the impact of ethanol high dose on rats' offspring induces a well pronounced increase of plasma viscosity, which is extremely important in blood circulation. The disruption of blood circulation causes a hypoxic condition (especially, in nervous tissues) and the disturbance of its functioning. This is the result of what has been seen in the behavioral experiments of female rats' offspring under the influence of ethanol high dose.