Free Behavioral Experiments: Case Study Sample

Schizophrenic mouse model proposed by Jackson Labs is a new model. In order to determine that it can be effectively used in our preclinical research for production of a new drug for schizophrenia, several cognitive tests were conducted, and this is a descriptive report on these tests.

Animals:
Six mice, each one weighing 20-30g were taken from Jackson lab, and housed in plastic cages. The cages were placed in rooms in which humidity and temperature could be controlled, and had a 12-h light/dark cycle for at least 1 week before experimentation. The free access of the mice was provided to food and water.

Novel object recognition (NOR) test:

Experimental methods used were similar to those used by Kunitachi et al. 2005. The same way, in the experiment six animals were used. They were kept in a black open field box from 3 days before the beginning of the experiment. On the 3rd day similar in size but different in shape and color were placed inside the black open field boxes, exactly 35.5 cm apart. For 5 minutes, the mice were free to explore the objects. They explored the objects by sniffing or touching them by any part of their bodies, except their tails, which is considered as exploring behavior. The exploration’s time was recorded. After removing the animal from the box, it was cleaned with 75% ethanol. The next day, the process was repeated again, but one of the objects was changed with a novel object. Again, the average exploration time of the object by animal was recorded. After repeating the trial for 6 times, the results showed that almost all six mice, for exploration of the familiar and novel objects spent approximately the same amount of time. We can come to this conclusion that it can be an induction of an impaired memory performance.
3. Pre-pulse inhibition (PPI) test:

Induced improvement of object recognition:

As previously described, the same experimental protocol as the experimental methods by Kunitachi et al. 2005 was used. The six animals were divided into two, 3 member groups.
The first group received 0.1 mg/kg/day of haloperidol and the control group intraperitoneally received 0.1 mg/kg/day. In an hour after receiving the medication, we conducted the object recognition tests. In result, the haloperidol group spent more time for exploration of the novel objects. However, the control group spent the same time to explore both objects.
5. Reversal of PPI disruption with clozapine:
Six animal models according to the experimental methods by Mansbach et al. 2001 were used to conduct the experiment. Half an hour before the conduction of the trials, three of the mice models received 1mg/kg of clozapine. The control group received 1mg/kg of saline subcutaneously. According to the results, the overall startle amplitudes were notably lower. However, the reflexive flinching in the clozapine group compared to control group was reduced.
6. Catalepsy test:
The experiment was conducted as each mouse had an upright position with its forepaws resting on a horizontal bar suspended and at approximately 10 cm height. The latency of each mouse including the removing the forepaw and climbing down to normal position was recorded. Those ones did not respond within 90s were removed from apparatus, and assigned to 90s latency. A 20 S immobility was considered as the criterion for the presence of catalepsy. Haloperidol, risperidone, ziprasidone and clozapine after doses of 0.1, 1.0, 3.2 and >56 mg/kg, Sc, can result in significant catalepsy. Based on these results we may state that until now the model is acceptable.

Conclusion:

The impairments of memory performance, catalepsy, and disrupted pre-pulse inhibition are the characteristics of schizophrenia. These signs were shown by The Jackson lab mice models. From the other hand, these dysfunctions were treated and reversed by using antipsychotics clozapine and haloperidol in an acute treatment. The results of the experiment were the same as older experiments with the same experimental protocols conducted before. In conclusion, I assume that this method can be considered as a reliable novel schizophrenic model, and as an experimental tool for conducting pre-clinical experiments for test and development of new antipsychotic drugs. Therefore, I strongly recommend this model to be used. In other words, the usage of the model for the company is reliable and positive.