Selective involvement of non-histone chromatin proteins in the reproduction of averse reaction to food in snail

Participation of the brain-specific non-histone chromatin proteins Np-3.5 in the reproduction of an averse habit to certain kind of food was studied in experiments onHelix lucorum. Antibodies to these proteins were found to completely suppress the behavioral reactions and responses of the defensive behavior command neurons evoked by a presentation of a certain conditioning stimulus: a carrot. The action of the antibodies was specific, as they did not change the snail's reactions to presentation of another conditioning stimulus: an apple. The effect developed 1.5 h after the administration of antibodies to Np-3.5, and remained for 80–110 min, with subsequent complete restoration of the conditioned reflex. The antibodies to Np-3.5 did not affect the nutritive behavior of untrained snails. The antibodies to Np-3.5 were found to label cytoplasm in the command neurons, whereas in the snails trained to reject carrot the label appeared in the nuclei of the cells. It has been suggested that the Np-3.5 proteins selectively participate in the molecular-genetic processes responsible for neurophysiological mechanisms of an information draw from the long-term memory.     

Effects of intraventricular administration of cholecystokinin octapeptide sulfate ester and unsulfated cholecystokinin octapeptide on active avoidance and conditioned feeding behaviour of rats

The effects of cholecystokinin octapeptide sulfate ester (CCK-8-SE) and unsulfated cholecystokinin (CCK-8-NS) were studied following intraventricular administration on active avoidance and conditioned feeding behaviour of rats. In the CCK-8-NS and CCK-8-SE treated animals the acquisition of active avoidance and conditioned feeding behaviour were considerably impaired compared to the control; furthermore, these peptides caused a facilitated extinction of active avoidance and conditioned feeding behaviour. The data suggest that cholecystokinin octapeptide is capable of modifying the fear and hunger motivated behaviours of rats.     

Interrelationship between grape snail alimentary and defense behavior command neurons]

Food stimulus (carrot juice), releasing feeding behaviour in intact snails, evoked spike discharges in giant meta-erebral cells (considered to be command neurones of feeding behaviour) and subthreshold EPSPs in giant parietal cells (command neurones of avoidance behaviour) of a half-intact preparation. Tactile stimulation, eliciting avoidance reactions in intact snails, evoked hyperpolarization in command neurones of feeding behaviour and a spike discharge in command neurones of avoidance behaviour. Spikes induced into either of command neurones produced no changes in activity of other command cells. Inhibition of command neurones of feeding behaviour is assumed to be the basis of behavioural choice when food and tactile stimulus are presented simultaneously.     

Regulators of Cell Division in Plant Tissues VUI. The Cytokinins of the Apple Fruit

The cytokinin activities of extracts of organs developed from the apple fruit bud were compared using the carrot phloem bioassay, and the identity of the cytokinins in the apple fruitlet was investigated. The activity of apple fruitlet extracts was slightly greater than the activity of pedicel extracts, and considerably greater than the activities of extracts of other organs. Extracts of the developing seeds of fruitlets were much more active than extracts of fruitlet flesh. Apple fruitlet extracts contained three principal cytokinins. One was identified as a 6-(substituted amino)purine and was either zeatin or some very closely related compound. The two other cytokinins exhibited the chromatographic behaviour of zeatin riboside and zeatin ribotide. A cytokinin extracted from vegetative apple shoots was chromatographically indistinguishable from zeatin.     

Effect of dalargin on the behavior of rats subjected to intrauterine ethanol exposure

Influence was studied of dalargin--synthetic analogue of enkephalin administered in early postnatal period to young rats with intrauterine ethanol injection, on their behaviour and conditioned activity. Parameters were established of spontaneous motor activity, behaviour in the open field, acquisition and preservation of conditioned reflexes of passive and active avoidance in experimental and intact rats, injected with dalargin. A reduction of sensitivity to corasol convulsive effect was observed under the influence of dalargin.     

Improved conditioned avoidance learning by oxytocin administration in high-emotional male Sprague-Dawley rats

OBJECTIVE: To examine anti-stress-like properties of oxytocin as a means to improve conditioned avoidance learning in a low-performing, high-emotional, stock of Sprague-Dawley male rats. METHODS: Adult male rats of two stocks of the Sprague-Dawley strain, designated Stock A and Stock B, were treated daily with oxytocin (1 mg kg(-1) s. c.) for 5 days preceding four daily conditioned avoidance acquisition sessions (approximately 20 trials per 15 min session). The Stock B animals were previously characterized as high-emotional based on [1] elevated plasma corticosterone, and lowered plasma oxytocin, levels and [2] decreased reaction time and an increased startle amplitude to an acoustic stimulation. Finally, [3] these animals were unable to acquire a conditioned avoidance response within 5 days of training. RESULTS: The Stock A animals rapidly and statistically significantly acquired the avoidance behaviour within 4 days of daily training, whereas Stock B animals did not improve over this time period. The avoidance performance of Stock B animals was markedly and statistically significantly improved by the oxytocin pre-treatment, whereas the performance of Stock A animals was not affected by the same oxytocin treatment. CONCLUSIONS: Pre-treatment with oxytocin markedly improved avoidance learning in the Stock B high-emotional animals. It is suggested that the improvement is due to previously demonstrated anti-stress-like properties of oxytocin, rendering the animals able to successfully cope with the demands of the conditioned avoidance situation.     

The effect of phenamine on the avoidance reaction in intact and striatectomized rats]

Various characteristics of a conditioned avoidance reaction were recorded in rats in a Y-maze. Small doses of d,l-amphetamine (0.5 mg/kg) facilitated avoidance response while large ones (5 mg/kg) worsened it. After ablation of the rostral part of the striatum, small doses of the drug had the same effect as before, but no deteriorating action of large doses was observed. The behaviour disturbance is related to the capacity of d,l-amphetamine for activating the nigro-striatal dopaminergic transmission.     

Effect of drugs of the nootropic class on rat behavior after deprivation of the paradoxical stage of sleep

Pharmacological analysis was used for studying the influence of 24-hour deprivation of paradoxical sleep by Jouvet method on retention of conditioned reaction of passive avoidance in rats. Psychotropic substances of different action were used for the analysis: nootropes as anti-amnestic--pyracetam (400 mg/kg), kleregil (100 mg/kg), centrofenoxin (50 mg/kg) and watersoluble salt of 3-oxypiridin derivative (3-OP) (50 mg/kg) and tranquilizer of bensodiazepine series phenazepam (1 mg/kg) as antistress and antiphobic. It was established that 24-hour deprivation disturbed the elaborated reaction but did not change the rate of emotionality and orienting-investigating behaviour of rats in the open field. Nootropes effectively restored the conditioned passive avoidance reaction while phenazepam had no effect. This allows to suggest that Jouvet method of paradoxical sleep deprivation elicits amnesia and its cause is not only stress but deficit of paradoxical sleep.     

The effect of phenamine and caffeine on caudate inhibition of conditioned reflex avoidance reactions in cats]

In cats with a preliminarily learned conditioned avoidance reaction, stimulation of the caudate nucleus inhibited behavioral response by lengthening its latency and reducing the number of conditioned reactions. Intensity of the inhibitory effect did not substantially depend on the localization of electrodes in the head or body of the nucleus and weakened within a few experimental days. D,1-amphetamine (0.5 to 4 mg/kg) and caffeine (10 to 10 mg/kg) suppressed the caudate inhibition, but the action of the drugs was manifested in different ways. The influence of large doses of d,1-amphetamine was characterized by a serious disturbance of behaviour and caudate inhibition of conditioned responses.     

Safe From Harm: Learned,Instructed, and Symbolic Generalization Pathways of Human Threat-Avoidance

Avoidance of threatening or unpleasant events is usually an adaptive behavioural strategy. Sometimes, however, avoidance can become chronic and lead to impaired daily functioning. Excessive threat-avoidance is a central diagnostic feature of anxiety disorders, yet little is known about whether avoidance acquired in the absence of a direct history of conditioning with a fearful event differs from directly learned avoidance. In the present study, we tested whether avoidance acquired indirectly via verbal instructions and symbolic generalization result in similar levels of avoidance behaviour and threat-beliefs to avoidance acquired after direct learning. Following fear conditioning in which one conditioned stimulus was paired with shock (CS+) and another was not (CS−), participants either learned or were instructed to make a response that cancelled impending shock. Three groups were then tested with a learned CS+ and CS− (learned group), instructed CS+ (instructed group), and generalized CS+ (derived group) presentations. Results showed similar levels of avoidance behaviour and threat-belief ratings about the likelihood of shock across each of the three pathways despite the different mechanisms by which they were acquired. Findings have implications for understanding the aetiology of clinical avoidance in anxiety.     

Effect of hormones of the neurohypophysis on different types of behavioral responses in the rat

In experiments on male rats arginyl-vasopressin (AVP), lysyl-vasopressin (LVP) and vasotocin (VT) in doses of 0.005-0.010 mg/kg decreased motor activity and emotional behaviour in the open field test. In a dose of 0.001 mg/kg AVP significantly accelerated the elaboration of active avoidance; oxytocin delayed it, but LVP and VT had no significant influence. AVP also somewhat attenuated the elaboration of passive avoidance. None of the four studied peptides significantly affected the rate of elaboration of conditioned food-rewarded reaction to place.     

The retroactive action of paradoxical sleep deprivation and immobilization stress on the mechanisms of memory and passive avoidance in rats

Influence was studied of 48-hours deprivation of paradoxical sleep (DPS) and immobilization stress on conditioned reaction of fear and security--components of passive avoidance conditioned reflex (CRPA), with simultaneous studying of vertical, horizontal activity, grooming reactions and defecations in an illuminated chamber. The obtained results allow to conclude that DPS inhibits reproduction of memory traces of fear reaction but intensifies the process of learning and activity of memory traces of security reaction. Depending on condition of CRPA elaboration, DPS may disturb or, on the contrary, prolong preservation of passive avoidance. It has been found that the immobilization stress does not influence CRPA preservation and does not weaken the reaction of fear but increases the horizontal activity. It is suggested that the observed changes in behaviour and trace processes are connected with disturbance of sensory informational homeostasis of the nervous system at DPS.     

The long-term effect of acute hypoxic hypoxia on shuttlebox avoidance learning in rats

Long-term influence was studied of the acute hypoxic hypoxia seance on rats behaviour in situation of elaboration of the conditioned reaction of active avoidance of electric shocks in shuttle chamber. It was found that in 2.5-3 months after the hypoxia seance, the experimental animals significantly differed from the intact controls by dynamics of CR elaboration (rats which had hypoxia were ahead of the control ones) and by distribution of the conditioned reactions latencies (for experimental animals this distribution was shifted to minor values). The character of these behavioural shifts coincided with that observed in the group of rats with local unilateral hippocampus lesion. The obtained results and numerous data presented in literature on the influence of the hippocampus lesion on animals shuttle avoidance learning, allow to conclude that the seance of hypoxic hypoxia leads to the disturbance of the hippocampus function. This conclusion conforms to the data on diffusive death of the hippocampal and neocortical neurones as a result of hypoxia action.     

The effect of DMCM and diazepam on the behavior of rats subjected to ethanol exposure in the prenatal period]

White rats were given 4 g/lag daily of 40% ethyl alcohol from the 5th till the 20th day of pregnancy. Males of the off-spring from the 5th till 19th day were subjected to treatment with 0.6 mg/kg DMCM (4-ethyl-6, 7-dimethoxy-beta-carboline-3-carboxylate methyl ether) or 2.5 mg/kg of diazepam daily. It has been shown that both drugs normalize increased locomotor activity; treatment with DMCM corrects passive avoidance conditioned reflex retention; both drugs restore active avoidance conditioned reflex elaboration in rats alcoholized prenatally. Moreover, treatment with DMCM or diazepam restores correlations between behaviour indices and binding of 3H-diazepam which have been altered by prenatal alcoholization.     

Cellular reactions to elaboration of a backward conditioned connection in Helix lucorum

After 10-15 food stimuli paired with electrical shock in semi-intact snail preparation, responses to strong tactile stimuli identified feeding behaviour neurones were studied. Inhibition evoked by tactile stimulation in these cells before learning procedure disappeared and in some cases noxious stimulus evoked synaptic activation corresponding to feeding reactions in the intact animal. Changes in second-order sensory neurones pre-synaptic to the command neurones of avoidance behaviour are suggested to be the mechanism of forward conditioned connection as well as the mechanism of backward conditioned connection.     

Food-attraction conditioning in the snail,Helix pomatia

Adult pulmonate snails (Helix pomatia) were released equidistant between two types of food, carrot and potato, respectively. Naive snails moved in different directions and did not locate either food above chance, although both foods were readily eaten upon direct contact. After a single carrot feeding episode, 75% of the carrot-fed snails moved directly towards the carrot and ate it. Conversely, potato-fed snails located the potato in 67% of the cases. Snails that were fed apple or lettuce behaved like naive animals, with the majority of animals (75% in both cases) locating neither the carrot nor the potato.The ability of snails to locate this particular food after a single feeding episode was maintained for at least 11 days, provided that the snails were not exposed to other foods in the interim. If the animals were fed a different food (but still tested for food-finding ability to the initially conditioned food) their orientation preference decreased gradually over a period of 5 days.Although the snails' orientation is based upon olfactory cues, exposure to food odor alone is not sufficient to enable food-finding; additional feeding related stimuli are necessary.These findings indicate that Helix do not possess a predisposition for the foods tested, and further suggest that processes underlying food-finding and food selection are strongly influenced by learning experiences. The conditioning phenomenon underlying food-finding behavior has been called Food-Attraction Conditioning, and appears to be a crucial link between the ecologies of learning and foraging behaviors. The accessibility of the snail's nervous system should permit neuronal analysis of the mechanisms underlying such a unique and complex learning phenomenon.     

A field test for host fruit odour discrimination and avoidance behaviour for Rhagoletis pomonella flies in the western United States

Prezygotic isolation due to habitat choice is important to many models of speciation-with-gene-flow. Habitat choice is usually thought to occur through positive preferences of organisms for particular environments. However, avoidance of non-natal environments may also play a role in choice and have repercussions for post-zygotic isolation that preference does not. The recent host shift of Rhagoletis pomonella (Diptera: Tephritidae) from downy hawthorn, Crataegus mollis, to introduced apple, Malus domestica, in the eastern United States is a model for speciation-with-gene-flow. However, the fly is also present in the western United States where it was likely introduced via infested apples ≤ 60 years ago. R. pomonella now attacks two additional hawthorns in the west, the native C. douglasii (black hawthorn) and the introduced C. monogyna (English ornamental hawthorn). Flight tunnel tests have shown that western apple-, C. douglasii- and C. monogyna-origin flies all positively orient to fruit volatile blends of their respective natal hosts in flight tunnel assays. Here, we show that these laboratory differences translate to nature through field-trapping studies of flies in the state of Washington. Moreover, western R. pomonella display both positive orientation to their respective natal fruit volatiles and avoidance behaviour (negative orientation) to non-natal volatiles. Our results are consistent with the existence of behaviourally differentiated host races of R. pomonella in the west. In addition, the rapid evolution of avoidance behaviour appears to be a general phenomenon for R. pomonella during host shifts, as the eastern apple and downy hawthorn host races also are antagonized by non-natal fruit volatiles.     

‘Does my Diet Affect my Perfume?’ Identification and Quantification of Cuticular Compounds in Five Drosophila melanogaster Strains Maintained over 300 Generations on Different Diets

Cuticular hydrocarbons (CHCs) in Drosophila melanogaster represent the basis of chemical communication being involved in many important biological functions. The aim of this study was to characterize chemical composition and variation of cuticular profiles in five D. melanogaster strains. These strains were reared for approximately 300 generations on five diets: standard cornmeal medium and substrates prepared with apple, banana, tomato, and carrot. Differences in quantity and/or quality in CHCs were assumed as a result of activation of different metabolic pathways involved in food digestion and adaptations to the particular diet type. In total, independently of sex and strain, 66 chemical compounds were identified. In females of all strains, 60 compounds were identified, while, in males, 47 compounds were extracted. Certain new chemical compounds for D. melanogaster were found. MANOVA confirmed that CHC amounts significantly depend on sex and substrates, as well as on their interactions. Discriminant analysis revealed that flies belonging to ‘apple’ and ‘carrot’ strains exhibited the most noticeable differences in CHC repertoires. A non‐hydrocarbon pheromone, cis‐vaccenyl acetate (cVA) also contributed to the variation in the pheromone bouquet among the strains. Variability detected in CHCs and cVA may be used in the explanation of differences in mating behaviour previously determined in analyzed fly strains.     

大鼠尾壳核的GABA能传递在条件性行为调控中的作用

本工作采用了行为和脑内注射相结合的方法研究了大鼠尾壳核的 GABA 能传递在条件性行为调控中的作用。在分辨学习的基础上训练大鼠完成条件性回避任务,以比较药物对分辨学习和条件性回避的不同效应。实验结果表明,于大鼠双侧尾壳核内分别注入 γ-氨基丁酸(GABA)(每侧100μg/μl)和 GABA 受体激动剂蝇蕈醇(Muscimol)(每侧0.1μg/μl)后可暂时抑制条件性回避反应的出现,但分辨学习无明显影响。作为对照,于尾壳核内注入等量的生理盐水则既不影响条件性回避反应,也不影响分辨学习。在条件性回避反应被 Muscimol抑制后于尾壳核内再注入 GABA 受体阻断剂印防己毒素(PTX)(每侧0.1μg/μl)则可拮抗Muscimol 的行为抑制效应,即条件反应的出现率可恢复到或接近注射前水平。实验结果表明,大鼠尾壳核的 GABA 能传递在条件性行为调控中的重要作用。     

The effect of single maximal physical loading on the emotional behavior of rats

In experiments on 250 Wistar female rats the influence was studied of a single maximum and submaximum physical loads on the emotional behaviour and the state of conditioned activity. It has been established, that as a result of maximum possible run of the animals depression takes place of orienting investigatory activity in conditions of the "open field" and disturbance of elaboration and reproduction of the conditioned reflex of two-way avoidance. Normalization of these parameters took place in 48 hours after the maximum load action. Analogous effect was observed in the period of aftereffect of the submaximum physical load, characterized by lowering of the level of behavioural activity in the "open field", disturbance of the elaboration of two-way avoidance as a result of presumable increase of functional tonus of the brain inhibitory systems.