A Necessary Evil

A Necessary Evil?

Modelling Depression in Rodents

As we move on in the modern age we grow and learn many things about science- we discover new things, new solutions to old problems and help people get better- these are the main focus of medical science. This broad field of medicine also includes disease or disorders related to the human brain. But before any drug that works effectively on any disease regarding the human brain is put into the market, it goes through a battery of tests. One of the most important being- testing it on animals, majorly rodents. Testing it on mammals is important so as to figure out the effect and efficiency of the drug on the mammalian brain, but at what price? Researchers use rodents- most commonly mice or rats, as the proverbial sacrificial lambs. These drugs and the tests have a huge possibility of killing the rodents, but we still continue doing it- this has been accepted as a necessary evil, but the question remains in many minds- what result could possibly justify the means? And how relevant is it?

Major depressive disorder (MDD) is one of the leading medical problems in the world. Approximately, more than 340 million people suffer from major depressive disorder (MDD) worldwide (Cryan and Slattery, 2014). Despite the prevalence of this disorder the understanding of it is still fairly basic and underdeveloped as compared to other many chronic diseases. One of the major causes for this being the difficulty in closer study of the live human brain (Krishnan and Nestler, 2009). Finding a cure, or at least making a dent in this problem is important. People need to understand the disease so it can be countered. As the study of MDD on humans would be considered unethical, the researchers manipulate rodents to understand it better.  

One important question at this point is why use rodents? There are four major reasons for which rodents are preferred for the research experimentation. One is rodents are easy to house and maintain. They have a short life-span and reproduce quickly- this way many generations can be studied. Two being, mice and rats are inexpensive and easy to buy. The third reason is that, most of these rodents are almost genetically identical, making the results obtained from the experiments more consistent. The last reason being, these rodents are behaviourally, genetically and biologically similar to humans. All the above reasons make rodents like rats and mice the perfect specimens to study the effector drugs that will later be administered to humans. These drugs can be mixed in the water or the food pellets of these rodents, so as to administer it easily.      

There are limitations to what the research of rodents can achieve. Although neurobiological basis of depression can be studied in detail using rodents, the expression of feelings involved cannot be captured (Dwivedi et al., 2017). There are various animal models that can be used to study depression which have certain resemblance to the human situations  (trauma) that may lead to MDD. “Overall, animal models that can elucidate the neurobiology of depression, allow the testing of novel neurobiological hypotheses, and have translational value, can be applied in humans” (Dwivedi et al., 2017). In this case the advantages overweigh the moral argument made against the precise of sacrificing of rodent for the perceived betterment of human race as a whole.

Science can build on past experiences- failures and successes, to improve, but it cannot predict everything, sometimes the results of any experiment can be shocking. Thus, simply theorising is not enough, the experiments need to be done by the researchers to get concrete results. Conducting such researches on humans would be considered unethical and thus the only method left is to conduct research on animals. It is not the best way, or the most moral one, but one thing is clear, there are many lives at stake and for humans rodents are far less important that their own health and living. 

BIBILOGRAPHY 

1. David A. Slattery, John F. Cryan, The Ups and Downs of Modelling Mood Disorders in Rodents, ILAR Journal, Volume 55, Issue 2, 2014, Pages 297–309, https://doi.org/10.1093/ilar/ilu026

2. Krishnan, V., & Nestler, E. J. (2008). The molecular neurobiology of depression. Nature, 455(7215), 894–902. doi:10.1038/nature07455

3. Melina, R (2010. November 16). Why Do Medical Researchers Use Mice?. https://www.livescience.com/32860-why-do-medical-researchers-use-mice.html 

4. Wang, Q., Timberlake, M. A., 2nd, Prall, K., & Dwivedi, Y. (2017). The recent progress in animal models of depression. Progress in neuro-psychopharmacology & biological psychiatry, 77, 99–109. doi:10.1016/j.pnpbp.2017.04.008