3.5.3 Pharmacology I
Lab 12 Collection of blood from orbital sinus of rats and separation of RBC (Cont'd...)
Mice are used when very small amount of blood is needed for experimental purpose (eg. to measure blood glucose level). Rabbits are used when large amount of blood or multiple collection of blood is required (eg. to determine plasma protein concentrations, effect of anti cancer drugs on blood profile for long term). Rats are used when about 1-2 ml of blood is required (eg. to determine the drug induced haemolysis). Here we have explained one of the popular methods of collection of blood (puncturing orbital plexus of rats) and the method of preparation of dilute RBC sample to use in pharmacological studies.
Healthy Wister rat (wt about 160-180g.)
Glass Capillary tube (0.8 mm diameter), Polypropylene tubes-5ml. (two), Closed chamber, Centrifuge, Pipette, Balance, pH meter, Stirrer, Cotton
Anasthetcs (Diethyl ether-1.9% or halothane-2-3%), Double distilled water, di-sodium hydrogen phosphate, sodium di-hydrogen phosphate, Sodium chloride (NaCl), Tri-sodium citrate (TSC), Antibiotic solution.
Step 1: Preparation of isotonic Normal saline: Weigh 0.9 gm of NaCl and add in 100 ml. of double distilled water to prepare 100 ml. of NS (0.9% w/v).
Step 2: Preparation of Phosphate buffer saline (100 mM, pH 7.4): Weigh and dissolve disodium hydhogen phosphate and sodium di hydrogen phosphate in normal saline to prepare 100 mM, 100 ml. and 50 ml. of these solutions respectively. Dissolve the Adjust the pH (7.4) of the buffer (PBS) by adding the second one in the first one.
Step 3: Preparation of tri-sodium citrate (TSC) solution: Add 1 ml. of TSC (1-2%) in 10 ml. of normal saline or PBS to get an anticoagulant solution.