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Biomedical subjects

V V Andrianov

Publications and source records attributed to V V Andrianov.

At least 37 records · Page 2Linked to original sources
PubMed1985

[Effect of the enzyme plasmin on blood coagulation in fish].

The influence of plasmin on blood coagulation in fishes has been studied. The plasmin administration in dose 250 conditional units has been shown to evoke hypercoagulation already on the 5th minute after injection. This defence reaction on the plasmin excess in blood flow was excluded by the preliminary administration of alpha- as well as beta-adrenoblocators. Subtle differentiation of adrenoreceptors is supposed to be absent in fishes, nevertheless they play a definite role in regulation of hemostasis system.

Adrenergic alpha-Antagonists↗
PubMedDate not supplied

The interaction of mediators with the processes of protein synthesis in neurons of the visual cortex in the goal-directed behavior of cats.

The chemical sensitivity of neurons of the visual area of the cerebral cortex of cats at sequential stages of food-procuring instrumental behavior, formed under the conditions of intraventricular administration of a protein synthesis blocker, cycloheximide, was investigated in the present study. It was demonstrated that in animals with cycloheximide there is a low level of chemical sensitivity of cortical neurons to microiontophoretically applied solutions of acetylcholine and norepinephrine. As compared with intact animals, in the animals with cycloheximide the number of neurons reacting with a change in impulse activity at the stages of instrumental behavior and the number of areactive cells did not depend on the nature of the applied neuromediator.

Acetylcholine↗
PubMedDate not supplied

Neuromediators in the neuronal mechanisms for attention and the perception of visual information during food-seeking behavior.

Neurons of the visual cortex were investigated in experiments with cats during the expectation of and at the time of milk presentation in a feeder. The milk was delivered either as a result of the animal pressing a pedal or extraneously, without pressing. It was determined that the presence of the directed visual attention of the animal towards the site of reinforcement appearing after pedal pressing is accompanied by an increase in the level of the impulse activity of individual neurons. The activation of cortical neurons at the time of the perception of the appearance of milk in the feeder was also pronounced in cases of expected reinforcement. The neuromediators tended to alter the discharge activity of individual neurons in both experimental situations.

Acetylcholine↗
PubMedDate not supplied

Influence of norepinephrine, acetylcholine, and their blockers on the activity of cortical neurons in goal-directed behavior.

The neurochemical mechanisms of the central organization of sequential stages in the formation of a goal-directed behavioral act were investigated by means of the microiontophoretic application of biologically active substances to individual neurons of the cerebral cortex of cats. It was demonstrated that the dynamics of the discharge activity of the neurons at particular stages of the behavioral act exhibited a contradictory character when neuromediators and their antagonists were applied. At the same time, differences in the impulse activity were more pronounced against the background of the application of propranolol and atropine than of norepinephrine and acetylcholine.

Acetylcholine↗
PubMedDate not supplied

The processes of anticipation and evaluation of the results of behavior and their cellular neurochemical mechanisms.

The cellular neurochemical mechanisms of the goal-directed activity of cats under free behavior conditions were studied using the method of the microiontophoretic application of biologically active substances to individual neurons of the visual area of the cerebral cortex. Two experimental situations were used in the study. The first consisted of the alternation of the animal's instrumental reactions in the form of pedal-pressing with following reinforcement and of unexpected deliveries of milk in the food dispenser, and the second consisted of the alternation of the instrumental reactions with following reinforcement and of such reactions without reinforcement. An association was demonstrated of the cellular neurochemical mechanisms with the processes of the anticipation, perception, and evaluation of the results of the goal-directed activity.

Animals↗
PubMedDate not supplied

Neurochemical mechanisms of the participation of individual neurons in the processes of anticipation and evaluation of the results of behavioral activity.

The neurochemical mechanisms of the participation of cerebral cortical neurons of cats were investigated in this study at various stages of the food-procuring behavior during their performance of an instrumental motor act and in instances of the unexpected appearance of a portion of milk in the food dispenser. The technique of the microiontophoretic application of agents to the cortical neurons was used in this study. It was demonstrated that the neurons exhibit varied chemical sensitivity to different agents in the period of expectation of reinforcement and at the moment of the appearance of the portion of milk. The dynamics of the impulse activity depended on the level of activity of the protein-synthesizing apparatus of the neurons.

Animals↗
PubMedDate not supplied

Characteristics of the chemical sensitivity of cerebral cortical neurons at the stages of food-procuring behavior of cats as a function of the quality of reinforcement.

The chemical sensitivity to the principal neuromediators of neurons of the visual area of the cerebral cortex was investigated at sequential stages of instrumental behavior in this study using the method of the microiontophoresis, in two experimental situations. In the first of these a portion of milk was used as the reinforcement; in the second, a portion of meat powder. It was demonstrated that the number of universal neurons decreases against the background of the application of norepinephrine and acetylcholine in behavioral acts with qualitatively different food reinforcements. At the same time, the number of neurons that are areactive at all stages of the behavior increases in the situation involving milk reinforcement, while it decreases in the situation involving meat reinforcement.

Acetylcholine↗
PubMedDate not supplied

The electrical characteristics of command and motor neurons during acquisition of a conditioned defensive reflex and formation of long-term sensitization in snails.

The mechanisms of the acquisition of a conditioned defensive reflex and formation of long-term sensitization were studied at the level of an analysis of the electrical characteristics of defensive behavior command neurons and motor neurons which open and close the pneumostoma. Significant decreases in membrane and threshold potentials were seen in command neurons in response to acquisition of the conditioned defensive reflex and formation of long-term sensitization, along with further decreases in these parameters in snails which were trained after long-term sensitization. Changes in the critical level of depolarization and amplitude of action potentials were insignificant. The changes observed here provide evidence for an increase in the membrane excitability of command neurons. Similar changes were not seen in motor neurons.

Action Potentials↗