The rodent model in inflammation is not the same as humans.
there have been more than 1,000 drugs (So what are they?)aimed at preventing brain damage that have failed to work in people, even though they worked well in mice or rats, said study researcher Dr. Michael Tymianski, of the Toronto Western Hospital Research Institute in Canada.
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Reason 1 is here;
Why Animal Experimentation Doesn't Work -- Reason 1: Stressed Animals Yield Poor Data
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Reason 2 is here;
Why Animal Experimentation Doesn't Work -- Reason 2: Animals Don't Get Human Diseases
Selected paragraphs are here:
Let's take a look at stroke experiments in animals to examine how they strike out. In humans, stroke is usually caused by the gradual narrowing of a blood vessel to the brain by atherosclerosis or by a blood clot that developed in another part of the body. Animals in labs don't naturally get strokes. Experimenters artificially induce strokes by methods such as clamping off major blood vessels in animals' brains or artificially inserting clots into their vessels. Here are the problems with this:
Diseases are diseases in context. In humans, stroke is usually linked to pre-disposing conditions such atherosclerosis, high blood pressure, and diabetes.
Strike 1: Artificially inducing stroke in animals does not recreate the complex physiology that causes the natural disease in humans, which may develop over decades.
Experimenters try to recreate the underlying human conditions such as diabetes in animals. However, these underlying conditions are usually also artificially induced in animals, and as we saw with diabetes, are often wrong anyway.
Strike 2: Animal stroke models don't usually include the underlying conditions, which contribute to human stroke.
Strike 3: Artificially inducing in animals the underlying conditions that lead to human stroke does not replicate the processes that occur in humans.Recognition of each difference between animal models and human diseases leads to renewed efforts to eliminate these differences. But in trying to recreate the complex physiology behind the human diseases, experimenters try to reproduce the complex physiology of the underlying conditions, which are just as difficult to accomplish. Thus animal experimenters are continuously going around in circles.
Stroke is probably one of the easiest human diseases to try to recreate in animals. Yet, over 150 stroke drugs found effective in animal stroke models failed in humans (1).
1. Macleod M. What can systematic review and meta-analysis tell us about the experimental data supporting stroke drug development? Int J Neuroprot Neuroregener 2005; 1: 201
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