Shuttle box

Elevated plus-maze Social interaction test Light/dark shuttle-box... 

Post-intoxication incapacitation The post-intoxication incapacitation was measured immediately after most symptoms disappeared, 24 hours, and one week after the intoxication. However, one day after soman intoxication no animals from the PYR group were available. Since the un-pretreated animals all died very shortly after soman no post-intoxication incapacitation was tested in these animals. The shuttle-box performance declined after soman intoxication with approximately 60% in all animals pretreated with PHY and SCO or PC. This decrease of performance was significant in the groups treated with a post-intoxication therapy (not... 

Pretreatment with PYR did also not prevent the animals from postintoxication incapacitation. There was no response of the startle reflex and these animals did not perform in the shuttle box task. Animals pretreated with PHY+SCO or PHY+PC were in a much better condition concerning incapacitation. Remarkably, the addition of a post-intoxication therapy did also not improve the efficacy on incapacitation in animals pretreated with PHY+SCO. 

Ginseng extract improves the spatial learning performance of aged rats in an eight-arm radial maze and operant discrimination task (Nitta et al. 1995). It also improves memory performance in active-avoidance (shuttle-box) and passive-avoidance (step-down) tasks, and reinforces staircase-maze learning in both young and aged rats. (Petkov and Mosharrof 1987 Petkov et al. 1990 Petkov et al. 1992). The effects were also very dose dependent, with inverted U-shape dose-response curves. 

If in instrumental conditioning a response is not followed by a punishment, but its absence, animals will increase this response in order to minimise punishment. In active avoidance tasks, for instance, animals have to show a distinct behavioural response in order to avoid a punishment. Typical examples would be shuttle-box experiments and jump-up avoidance. A shuttle box consists of two compartments that are connected by a sliding door. The punishment will be signalled by either a tone or a light stimulus (CS). Animals have to leave the compartment in which the CS was presented within a selected amoimt of time, after which the CS would be followed by a footshock. In the pole-jump test, the occurrence of the footshock will be signalled by a tone or hght stimulus as well. Animals can avoid the punishment if they jump onto a vertical wooden rod. 

Vecsei L, Widerlov E Effects of intracerebroventricularly administered somatostatin on passive avoidance, shuttle-box and openfield activity in rats. Neuropeptides 12 237-242, 1988... 

Passive avoidance. This test involves the use of a shuttle box, in which animals can move between a light side and a dark side. After an acclimatization period, in which the animal can move freely between the two sides, it receives a mild electric shock while in the dark (preferred) side. During subsequent trials, the time spent in the safe side is recorded. 

CPP study was conducted in a shuttle box divided into two compartments (Opto-MAX , Columbus Instruments, Ohio, USA). Mice were placed after injection of METH or saline in one compartment and were placed after injection of saline in the other compartment the next day during the conditioning paradigm. 

CAR Acquisition and Performance of Rats in a Shuttle-Box. Actlv. Nerv. Sup. 14 163-164. 

To investigate the difference in sensitivity towards (-)-BPAP between the subcortical and cortical neurons of rats in vivo, we performed two series of experiments in the shuttle box. 

In the shuttle box the acquisition of a two-way CAR was analyzed during 5 consecutive days. The rat was put in a box divided inside into two parts by a barrier with a small gate in the middle, and the animal was trained to cross the barrier under the influence of a conditioned stimulus (CS, fight flash). If it failed to respond within 5 s, it was punished with an unconditioned stimulus (US), a footshock (1 mA). If the rat failed to respond within 5 s to the US, it was classified as an escape failure (EF). One trial consisted of a 15 s intertrial interval (IR), followed by 15 s CS. The last 5 s of CS overlapped the 5 s of US. At each learning session, the number of CARs, EFs and IRs were automatically counted and evaluated by multi-way ANOVA. 

To test a compound s ability to enhance the acquisition of CARs in the shuttle box, it is necessary to select proper training conditions. In the case in which the rat was trained with 100 trials per day, the acquisition of CARs reached an 80% level and the EFs approached or reached the zero level. To demonstrate the highly significant enhancer effect of (-)-BPAP on the mesencephalic catecholaminergic neurons in vivo, we trained the rat with 100 trials per day, blocked the acquisition of CARs by pretreating the rats with tetrabenazine, and restored the learning ability with the simultaneous administration of (-)-BPAP. Table 3.1 shows that (-)-BPAP antagonized the effect of tetrabenazine in the rats. 

Table 3.1. Because of its enhancer effect on catecholaminergic neurons, (-)-BPAP antagonized tetrabenazine-induced learning deficit in rats trained in the shuttle box...

Rats (in each group 4 males and 4 females) were trained at 100 trials daily for 5 days in the shuttle box. The performance on the fifth day of training is shown in the table. CAR conditioned avoidance response EF escape failure IR intersignal reaction Significance of combination (tetrabenazine + (-)-BPAP) vs tetrabenazine (ANOVA) P < 0.05, P < 0.02, P < 0.01, P < 0.001. 

Because of the bell-shaped concentration effect curve characteristic to the enhancer effect of (-)-BPAP (see Fig. 3.11), we used 10 doses of the compound, ranging from 0.000001 to lOmg/kg, to clarify the effect of (-)-BPAP on the cortical neurons. Table 3.2 demonstrates that none of the applied doses of (-)-BPAP was capable of changing the learning performance of rats in the shuttle box. In accord with the findings on cultured rat cortical neurons, the in vivo experiments confirmed that (-)-BPAP, the presently known most potent synthetic mesencephalic enhancer substance, is devoid of a specific enhancer effect on the cortical neurons. 

With all this in mind, our approach was that the modification of behavior of the rats trained in the shuttle box depends on the synchronous activation of different groups of cortical neurons in the brain for a proper period of time. The following method is suitable to test the validity of this approach. 

Treatment of rats with 1 mg/kg tetrabenazine, which blocks selectively and reversibly the reuptake of the catecholaminergic transmitters into their intraneuronal stores, depletes norepinephrine and dopamine from the end organs of the catecholaminergic neurons in the brain stem. Since the operation of the catecholaminergic brain engine is the condition sine qua non for the trial-and-error mechanism and thus for the success of reaching a goal, the acquisition of a CAR in the shuttle box cannot be detected in tetrabenazine-treated rats because of the blockade of the animal s ability to cross the barrier. 

In the first part of the experiment (Series A), groups of female rats (n = 8) were trained in the shuttle box from Monday until Friday with 100 trials/day for 5 consecutive weeks. The animals were treated subcutaneously, 1 h prior to measurement, either with 1 ml/kg saline (Group 1) or with 1 mg/kg tetrabenazine (Group 2). Following a 5-week training period (Series A), the animals were rested for 3 weeks and then trained again for 3 consecutive weeks (Se-... 

On the 5th day of the 3rd week of training in Series B, there was no difference even in the EFs between the two groups. It is obvious that rats treated with tetrabenazine learned similarly to the saline-treated rats, we were just unable to detect this modification of behavior because mesencephalic enhancer regulation was blocked in Group 2 by tetrabenazine treatment, and the rats were unable to operate in the shuttle box. 

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