Analgesic activity study of drugs by tail-flick method

5/5 - (3 votes)

BACKGROUND

Algesia (sensitivity to pain) can be induced by various ways to the animals. Painful response can be noted with and without pain killers (analgesics).

Analgesic drugs inhibit the sensitivity to pain.¹ Pain is induced by radiant heat applying on a selected spot generated by a beam of light.

REQUIREMENTS

Animals : Mice (20-25 g) or Rat (150-180 g)

Drugs : Morphine sulphate (5 mg/kg), inject i.p. 1 ml/100 g body weight,

Other drugs : Pentazocin (20 mg/kg, i.p.), Aspirin (100 mg/kg, p.o.)

Equipment : Tail flick analgesiometer, Mouse restraint

PROCEDURE

Weigh and mark the animals. Allow the animals to acclimatize. Hold the animal, gently cover with a glove to restrain.

Perform the experiment when the animal will be calm and without movement of tail. Ensure that the animals have no previous damage in the tail at the time of experiment.

Hold the test animal under heat source and press the start button. Heat will be applied not more than 3 cm from the tip. After application of heat, the animal will withdraw its tail with sudden flick.

Set a timer at the start of application of heat and note down the time of withdrawal of tail. The withdrawal of tail from the heat source is referred as tail flick latency.

Check the basal reaction time of animals and note down. When the reaction time reaches 10 sec will be considered maximum analgesia to avoid damage.

Start the experiment 30 min after drug treatment.² Reaction time after 15, 30, 45 and 60 min of drug treatment will be noted.

Calculate the percentage of increase in reaction time or index of analgesia at above time interval.

Observation table for analgesic activity study

Sl. No.	Body Weight	Treatment	Basal reaction time (sec)	Reaction time after 30 min of drug treatment

CONCLUSION

Prolonged latency time ensures relief of pain. From this experiment it can be concluded that the tested drug has analgesic activity.

REFERENCES

Tripathi KD. Essentials of Medical Pharmacology. 7^th edn, Jaypee brothers medical publishers (Pvt) Ltd, New Delhi; 2013.
Lalan BK, Hiray RS, Ghongane BB. Evaluation of Analgesic and Anti-Inflammatory Activity of Extract of Holoptelea Integrifolia and Argyreia Speciosa in Animal Models. J Clin Diagn Res. 2015;9(7):FF01–4.

Also read:

🔴 Would you like to attempt Labmonk Daily quiz? Click here

🔵 Check out Jobs & Exam Notices. Labmonk Notice Board

🔴 Labmonk Scholarships. Click here

🔵 Labmonk Blog. Click here

🔴 Do you need notes? Click here

🔵 Watch Career related videos on Youtube: Watch now !!

FAQs

What is the principle of tail flick method?

After application of heat, the animal will withdraw its tail with sudden flick. Set a timer at the start of application of heat and note down the time of withdrawal of tail. The withdrawal of tail from the heat source is referred as tail flick latency.

What does the tail flick test measure?

Heat will be applied not more than 3 cm from the tip. After application of heat, the animal will withdraw its tail with sudden flick. Set a timer at the start of application of heat and note down the time of withdrawal of tail. The withdrawal of tail from the heat source is referred as tail flick latency. Check the basal reaction time of animals and note down. When the reaction time reaches 10 sec will be considered maximum analgesia to avoid damage.

Which instrument is used to study the analgesic activity?

Tail flick analgesiometer is used for tail flick method and hot plate (Eddy’s hot plate) method is used for analgesic activity study.