Yes

http://www.journalsleep.org/articles/270101.pdf

http://www.journalsleep.org/Articles/260203.pdf

I agree with collegue - YES

It is indeed useful to do the animal studies to understand the effect of new molecules on different organs. Even though some are saying that in vitro (cell line) will replace the in vivo studies but you can not create the whole biological environment in single cell line.

The question is the same is true in study of molecular substance. But when we observe a certain activity of a herb which is given as a whole in form of juice or decoction, many a times the finding doesn't go inline with that of the clinical ones. Probably there is some defect in the methodology or some have the opinion that even though it is nearly the same mechanism of tissue and organs of the model still the living environment is different along with food intake. Hence the question is being asked.

Sure it is. Besides PK and tox studies, a substance has to be tested in vivo. Most targeted organs do not simply consist of one cell type, thus you can't extrapolate in vitro data to in vivo settings. F.i. you may see an effect of a substance in a liver cell line, but it may turn out that it doesn't work in primary hepatocytes, or that in vivo the substance gets metabolized by/or has higher affinity to Kupffer cells rather than targeting the desired hepatocytes. Another important thing: some cells loose specific enzymatic activities when isolated and cultured in vitro. Or: how would you test a spasmolytic substance for asthma in vitro, or a bile acid sequestrant in culture? Simply doesn't work.

I clearly agree with the experimentation with respect to different toxicity studies like acute or chronic. Other than that assessment of the action with respect to different symptom of various diseases. With respect to you sir Ivan I do agree with the aspect that one can't extrapolate the in vitro data to in vivo settings because the cell line is different. I am speaking specially of in vivo studies as these are usually with assumption that the condition that is generated is similar to that seen in man.

• I believe it is must, as all the drugs meant for human use have to undergo clinical trials and for that perpose we need a data with preclinical studies. So doing preclinical studies with Animals of similar genes is very important and must be followed. 

Definitely, Plz refer the book-Terry P Kenakin (A Pharmacology primer) chap-1 for better insight. Any biological system has loads of complexities and hence, the input and output may vary to a considerable extent. The drug discovery process necessarily relies on testing of molecules in surrogate systems and the extrapolation of observed activity to all systems. The only way to do this is to obtain system independent measures of drug activity like affinity and efficacy apart from toxicity in animal models. Thus, it is important to go for in vivo studies as well.

Yes, presently it is a kind of compulsion in drug discovery and development process to do preclinical studies using experimental animals. However, there are many ethical controversies regarding extent of translation of preclinical results for further clinical development of the same drug candidate.

Considering the above controvesies, there are many theories given in order to provide alternatives for use of animals in pharmacological experiments. One of them is a famous '3R concept' i.e. R = Complete Replecement of animals by using some other alternative, R = In case replecement is not possible, Reduction in the number of animals being used, R = If the other two approaches are not feasible, Refinement of the sufferings of the animals being used through introduction of advanced techniques.  

I completely agrre with the suggestions given by Amrit SIngh, Suchita Dubey and all. The topic of using animals in research is quiet complicated now a days as it has both pharmacological as well as ethical issues. For accomplishment of this pproperly government of India has Formed a Committe named CPCSEA (Committee for the purpose of control and and supervision of experiments on animals) which monitors such experimental work at any institute and this committe has suggested to from a Committee named IAEC (Institutional Animal Ethical Commiteee) which comprised of eminent people from research as well as social network.

In short, controlled scientifically supervised and monitored experiments on animals which are not repeat of previously conducted studies and which has a srong hypothesis should be allowed.

But Abdil Sir, I am asking about those medicines which are already having clinical use in the old treatises of various medical systems like Ayurveda and Unani.

Dear Mahesh, though these traditional medicine has long age old tradition of uses, there is no documented scientific evidence of their clinical effectiveness as well as safety which can be useful as per the norms of modern medicine usage. Hence such study and data will be helpful for global accepatance of such medicines.

Dear Mahesh, the most important reason to do pharmacological research in animals on compounds which are proven to be effective in humans, is helping to select better derivatives. However, animal pharmacology studies usually perform quite poorly in predicting efficacy against diseases in humans. Performing animal pharmacology studies is a good process towards scientific modesty. Nature is often more complex than we can even imagine.....

Yes. Specially in the field of nociceptive test in animals, it is not enough to evaluate clinical effects, but to analyze the mechanisms involved. Before analyzing possible mechanisms in humans, enough data must be obtained form animal models.