Conditioned Avoidance Response In Rats Research Articles

A note on the autoregressive process during the conditioned avoidance response in rats.

Es wurden Reaktionszeiten, die wahrend einer instrumentellen Konditionierung bei Ratten automatisch gemessen wurden, hinsichtlich ihrer Autokorrelations- und Spektraldichtefunktion untersucht. Die autoregressiven Oszillationen der Reaktionszeiten vom 4.–7. Tag des Trainings basieren auf einem nicht-zirkularenMarcov-Prozess.

The effect of anti-Parkinsonian drugs on haloperidol-induced inhibition of the conditioned-avoidance response in rats

Haloperidol (200 μg/kg s.c.) inhibited the conditioned-avoidance response (CAR) in rats. Amantadine HC1 (12.5–50 mg/kg i.p.) produced a dose-dependent reduction in this inhibition. The reduction produced by apomorphine (10mg/kg i.p.) was more transient, and that produced by l-DOPA (200 mg/kg i.p.) was less marked than that produced by amantadine. Benzhexol (10 mg/kg i.p.), atropine (10 mg/kg i.p.) and BRL 1288 (10 mg/kg i.p.) produced no significant effect. The role of central dopamine mechanisms in these responses and the possible use of this procedure in screening anti-Parkinsonian drugs is discussed.

1, 3-Diphenyl-5-(2-dimethyl amino propionamide) pyrazole塩酸塩 (AP-14) の薬理学的研究特に中枢神経に対する作用を中心として

At a high dosage, AP-14 depressed emotional behavior elicited by hypothalamic electrical stimulation in rabbits. Using the screening method for central acting drugs, AP-14 equalled that of chlormezanone in mice. AP-14 inhibited to some extent the conditioned avoidance response in rats. Analgesic action was demonstrated by electrical and ultrasonic stimulus methods in mice. Anti-inflammatory action of this drug was found to be more effective than that of aspirin, in rat paw edema induced by carrageenin.

Effects of cannabidiol and of diphenylhydantoin on the hippocampus and on learning.

Cannabidiol (3.5 mg/kg, i.p.) depressed hippocampal facilitation and posttetanic potentiation of evoked responses in rats, such, as had been reported before for diphenylhydantoin. Both diphenylhydantoin (80 mg/kg, i.p.) and cannabidiol blocked the increase of hippocampal RNA concentration caused by afferent stimulation, and depressed the acquisition of a conditioned avoidance response in rats. Neither drug affected the retention of such response when given by posttrial injection, nor the spontaneous locomotor activity of mice. The effects of both agents may be explained by the interference they have been previously shown to produce with the release of K+ from the hippocampus during stimulation. In fact, hippocampal facilitation and posttetanic potentiation and the RNA response to stimulation have been shown to be phenomena which depend on this K+ release, and have been attributed a role in learning.

Hippocampal Electrical Activity in Spontaneous Behavior and Active Avoidance Conditioning in Rats

The purpose of this study is to examine previous theories of hippocampal electrical activity in relation to behavior with special emphasis on VANDERWOLF's hypothesis, based on new data with rats as subjects, in which hippocampal activity was studied during spontaneous behavior patterns and active avoidance conditioning with MILLER-MOWRER box.The main results were : (1) Hippocampal EEG during spontaneous behavior.Theta rhythms of 79 Hz were clearly observed during such behaviors as searching and rearing without locomotion and walking forward or around, as well as during head and body movements without locomotion. When animals were awake but motionless, hippocampal EEG consisted of desynchronized activity was also observed.(2) Hippocampal EEG during active avoidance learning.Hippocampal theta activity was not produced by the presentation of CS (2000 Hz pure tone) in habituation trials. In avoidance training, CS elicited a clear train of theta activity (79 Hz) starting a few seconds before the occurrence of avoidance responses. In the final state of avoidance learning, theta activity occurred immediately after the onset of CS and theta frequency increased to 911 Hz just before shuttling to the next compartment.From these and other results, hippocampal theta activity was shown to be associated not only with voluntary movement as suggested by VANDERWOLF but also with arousal level or general attention level.

Some effects of response-independent shocks after unsignaled avoidance conditioning in rats

After extended unsignaled avoidance training, the majority of rats continued frequent responding during long periods when only response-independent shocks were presented. Most responses were shock elicited, i.e., followed immediately after shock. Response rates were directly related to both the frequency and the intensity of response-independent shocks. Responding continued to approximately the same extent, whether shocks were presented at fixed or variable intervals. Few responses were directed toward a second lever in the test chamber, even when the lever previously associated with avoidance was removed. When avoidance was scheduled on the second lever, the rats learned to avoid by operating it. Meanwhile, responding on the first lever became infrequent. Subsequently, when only response-independent shocks were presented, almost all responses occurred upon the lever initially associated with avoidance. Responding that was elicited by response-independent shocks was suppressed by response-dependent (punishment)_shocks of the same intensity. When punishment was withdrawn, recovery of responding occurred. An explanation of the results based upon shock-elicited behaviors is preferred to one stressing unextinguished avoidance responding.

Physiological disposition of isoergine [from Argyreia nervosa (Burm. f.) Bojer Convolvulaceae] and its effect on the conditioned avoidance response in rats

Physiological disposition of isoergine (d-isolysergamide, iso-LA) obtained from the seeds of Argyreia nervosa (Burm. f.) Bojer were determined in rat liver, brain and plasma. Method of determination involved the extraction of the drug from biological samples and quantitation of the compound by fluorometric analysis. The injection of 5 mg/kg, i.p., of iso-LA resulted after 5 min in peak levels in the liver (7.2 μg/g) and after 15 min in peak levels in the brain (1.2 μg/g) and plasma (1.9 μg/ml). After 120 min, 90% of the compound had disappeared from the tissues and plasma. The minimal dose required to produce a significant decrease in the conditioned avoidance response (CAR) was somewhat less than 5 mg/kg. The minimal brain level which interfered with the CAR was approximately 1 μg/g. Brain levels of iso-LA seem to correlate directly with changes in behavior suggesting that iso-LA, and not a metabolite, is the psychoactive agent.

Effectiveness of Tranquilizing Drugs in Rats Exposed to Mixed Gamma-Neutron Radiations

Chlorpromazine, triflupromazine, and chlordiazepoxide were studied for their effect on a conditioned avoidance response in rats at selected times following 500-, 1000-, and 10 000-rad whole-body doses of mixed gamma-neutron radiations. The ED50 of the drugs increased in the rats receiving 1000 rads and decreased in those receiving 10 000 rads when compared to unirradiated controls. Although the dose-respone curve may be altered in irradiated rats, the three drugs studied remained effective even after radiation doses associated with central nervous system damage.

Long term effect of vasopressin on the maintenance of a conditioned avoidance response in rats.

RATS subjected to posterior lobectomy are unable to maintain a shuttle-box avoidance response without reinforcement1, but normal behaviour can be restored to that of sham-operated controls by treatment with pitressin tannate in oil, a relatively crude extract of posterior and intermediate pituitary lobes. Long acting preparations of ACTH and α-MSH can also restore the normal rate of extinction of an avoidance response in posterior lobectomized rats2. Pitressin as well as ACTH analogues, including α-MSH, delay the extinction of an avoidance response also in intact rats3,4. Treatment with pitressin tannate in oil, however, preserves a conditioned avoidance response whether the treatment is given during acquisition or extinction, while ACTH or ACTH analogues inhibit extinction most markedly during the treatment period3. These observations suggest that the mechanisms by which pitressin and analogues of ACTH affect conditioned avoidance behaviour are basically different. The fact that rats treated with pitressin retain the avoidance response for a considerable time after treatment suggests that this preparation contains peptides which interfere with long term memory storage, but that peptides with a configuration like that of ACTH participate in short term (trial to trial) memory processes3.

The effects of ribaminol on the acquisition of a conditioned avoidance response in rats

Naive rats were given IP injections of saline or ribaminol either 30 min. before or daily for four consecutive days before training in a shuttle box. Rats injected with ribaminol 30 min. prior to testing showed a dose related decrement in learning performance. Rats injected for the four consecutive days were unaffected by treatment with ribaminol.

Acquisition of conditioned avoidance response in rats under the influence of addicting drugs.

Four groups of white rats, aged 8–12 weeks, were treated with morphine, d-lysergic acid diethylamide, dl-amphetamine and ethanol, respectively, while being trained in a conditioned avoidance response (CAR) schedule. Morphine caused deterioration in the acquisition of CAR, as manifested by significant increases in the number of training sessions required for 100% correct CAR and in the reaction time (RT), when compared to those of a control group. The RT decreased after withdrawal of morphine and was associated with a revival of the conditioned emotional responses (CER). LSD and ethanol insignificantly retarded the acquisition of CAR, while withdrawal of LSD caused significant increases in the RT, error and CER. Amphetamine facilitated the acquisition rate associated with increased CER; during withdrawal, the CER was negligible whereas the error increased significantly. In another series of rats, tolerance was seen to morphine and, to a less extent, to ethanol and amphetamine after 8–12 days of continued treatment; whereas the withdrawal effects lasted for 3–4 days only. These effects of the addicting drugs on conditioned learning are discussed in the light of their influence on the emotional responses of the animals and the degree of development of drug-dependence.

The effect of various antidepressant drugs upon the tetrabenazine-suppressed conditioned avoidance response in rats.

Rats were trained in a three-chambered discrimination box to avoid an electric shock which was preceded by the presentation of light. Tetrabenazine, at a subcutaneous dose of 6 mg/kg suppressed this conditioned avoidance response (CAR) without abolishing the unconditioned escape response (UER). The three classes of antidepressant drugs affected differently the tetrabenazine-induced suppression of CAR. The tricyclic antidepressants, imipramine and desmethylimipramine (DMI), did not prevent the suppression of the CAR while the monoamine oxidase (MAO) inhibitors, iproniazid and pargyline did. The stimulant drugs d-amphetamine and methylphenidate, in addition to preventing also reversed the effect of tetrabenazine. The action of two experimental compounds, butriptyline and Lu3-010 was also investigated.

Alterations in pain thresholds and avoidance conditioning in rats with septal lesions

Rats with septal ablations displayed lower jump thresholds for pain than sham-operated controls, but did not differ in open-field activity. Septal rats were poor two-way avoidance learners with a moderately strong UCS intensity on both a simple and a discriminated avoidance task. Septal lesions may affect avoidance performance by increasing the rat's responsiveness to painful stimuli, thereby disrupting behavior associated with an intense fear drive.

新向精神薬，Oxazolazepamの薬理学的研究(第I報)

Oxazolazepam showed marked taming effects in mice, hamsters, rats and monkeys. These effects were comparable to those of chlordiazepoxide. Oxazolazepam was somewhat more potent against convulsions induced by megimide and pentetrazol and convulsion of E1-strain mouse but was less potent against convulsions induced by strychnine and electro shock than chlordiazepoxide. On the decrease of spontaneous locomotor activity, muscular relaxation, ataxia and loss of righting reflex in mice and tolerance of taming effects in hamsters, oxazolazepam was definitely less effective than chlordiazepoxide. On the conditioned avoidance response in rats, emesis produced by apomorphine in dogs and tremorine induced symptoms in mice, oxazolazepam was not significantly inhibitory.

Attenuation and reestablishment of the cer by discriminated avoidance conditioning in rats.

Attenuation and reestablishment of the cer by discriminated avoidance conditioning in rats.

The effect of sleep altering environments upon the acquisition and retention of a conditioned avoidance response in the rat

The presence of severely restricted environmental conditions reported to produce marked alterations in sleep patterns, most notably REM sleep, had no effect upon the acquisition and the consolidation of a conditioned avoidance response in rats. However, those subjects who learned the response in the severely restricted environment showed a marked decrement in avoidance responding when retested from normal conditions. The reestablishment of the severely restricted environment was a sufficient condition for the return of performance during retest situations. Other environments produced no such effects. The correlation between changes in sleep behavior and performance was greater than the correlation between environment and performance. There is some factor (or factors) present in such environmental situations that manifests itself in two ways: external changes in sleep patterns and the development of a factor performance coupling. It is not known whether both phenomena share a common origin or whether they are independent events. The development of an environmental state dependency provides one possible explanation for some of the behavioral alterations seen following sleep-cycle disruption. The utilization of other techniques capable of influencing sleep is necessary to determine the factors relevant, in this environment, to the production of the changes noted.

Pemoline and magnesium hydroxide (PMH): Performance enhancement af ter ECS

In a double-blind study, PMH was demonstrated to enhance performance during acquisition of a conditioned avoidance response in rats following electroconvulsive shock. This antagonism of antegrade amnesia by PMH is interpreted as further evidence of enhancement of consolidation ofmemory processes.

Psychopharmacological activity of the active constituents of hashish and some related cannabinoids.

1. The psychopharmacological activity of Δ1-tetrahydrocannabinol, (I); Δ1(6)-tetrahydrocannabinol (4′ hexyl), (II); Δ1(6)-tetrahydrocannabinol, (III); 1-ethoxyhexahydrocannabinol, (IV); 8-ethoxy-iso-hexahydrocannabinol, (V); Δ1(6)-tetrahydrocannabinolic acid Me ester, Isomer I, (VI); Δ1(6)-tetrahydrocannabinolic acid Me ester, Isomer II, (VII); cannabigerol, (VIII); Δ1(6)-tetrahydrocannabinol (3′ hexyl), (IX); cannabichromene, (X); has been examined in a variety of animal species. 2. Compounds (I) and (III) caused severe motor disturbances and a stuporous state in dogs and ptosis, “tameness” and peculiar postural changes in monkeys. In the latter animal, compound (II) elicited similar effects. 3. Compounds (I) and (III) after intraperitoneal but not subcutaneous administration, suppressed the gerbil digging activity; reduced the rat conditioned avoidance response and induced a cataleptoid reaction in mice, rats and gerbils. In addition, compound (I) reduced the performance of mice on the rotating-rod. Both compounds, administered subcutaneously, induced a measurable ataxic gait in rats. 4. Amphetamine reversed the behavioural changes elicited by compounds (I) and (III) in monkeys, as well as the cataleptoid reaction in rats. 5. None of the other compounds provoked observable changes in any of the species studied. 6. It is suggested that Rhesus monkeys might serve as a suitable model for assessing the psychopharmacological activity of active cannabinoids.

Activity and learning in rats after magnesium pemoline.

Manesium pemoline enhances the learning of a conditioned avoidance response in rats. 24 hours later this enhancing effect is no longer significant. With the same doses, magnesium pemoline induces a marked hyperactivity. In an experimental situation of simple visual discrimination magnesium pemoline does not alter the performance of the animals but seems to bring about an abnormal fixation of certain types of behaviour.

The active sequence in the acth molecule responsible for inhibition of the extinction of conditioned avoidance behaviour in rats

The effect of structural analogues of the N-terminal decapeptide of ACTH on inhibition of extinction of a conditioned avoidance response in rats has been studied. Studies involving the relation between chain length and behavioural activity revealed that the sequence 4–10 is the shortest peptide which affects the avoidance response as potently as does the decapeptide. Although the presence of the sequence 1–3 is not essential for the behavioural effect, slight structural modifications within these 3 amino acids are accompanied by loss of activity.