I would suggest you to measure the pharmacological effect of your different formulations in rats by recording their blood pressure (BP).

One of the reliable and reproducible animal models of the Pharmacodynamic study for antihypertensive drugs is TELEMETRY METHOD. Briefly, a transmitter is surgically implanted in Rat abdomen and a delicate catheter is inserted and fixed in animal aorta and you will get the blood pressure records continuously from freely moving animal wirelessly through a receiver and software to your PC. So you could schedule through software to record BP as you need 24h/7days a week, to compare the effect of different antihypertensive drugs or different formulations on animal BP, looking for their potency or duration of action. However, this method is not simple and the whole setup will cost more.

The second method which could be used to measure rat BP is TAIL CUFF METHOD. This one is simple and not sophisticated but is not more reliable and reproducible.

Both of the above-mentioned methods are in vivo methods and the animals are intact.

If you decide to use any of these methods, I would give you more details.

Thanks a lot for your answer.....

Sir can you give me some details regarding the latter (Tail cuff) method....

Dr Behera,

Tail cuff method is a Non-Invasive Blood Measuring method which is named NIBP as well. In this method the rat BP is measured through its tail using a cuff similar to one is used to measure BP in human from arm. Please find below links for some works used tail cuff method to measure BP in rats:

1- http://www.europeanreview.org/wp/wp-content/uploads/2449-2456.pdf

2-http://link.springer.com/article/10.1007%2Fs11010-013-1848-7

3-http://www.ncbi.nlm.nih.gov/pubmed/17634759

You can find more works by using "rat blood pressure + tail cuff method" keywords in "pubmed" or any other databases.

Finally here is the link to have a look to the instruments and their specification needed in tail cuff method in ADInstrument site:

http://www.adinstruments.com/products/IN125R#overview

Do not hesitate to contact me for any further assistance.

Good luck

Thanks a lot sir for your suggestion....

Please see this link.....its free article.

Warm regards

http://www.hindawi.com/journals/bmri/2015/528757/