Third Year B.Pharm

1. Effect of saline purgative on frog intestine
Experiment No. 5
Pharmacology-III Practical
B.Pharm Semester-VI
Dr. Sameer H. Sawant,
Assistant Professor Pharmacology,
Dr. Sameer H. Sawant, SIOP

2. References:
• Shivsharan B. Dhadde. Handbook of Experimental
Pharmacology. Studium Press (India) Pvt. Ltd. New Delhi
(2019). Page no. 17-18
Dr. Sameer H. Sawant, SIOP

3. Important You tube Link
• https://www.youtube.com/watch?v=rH-n9ugHPHk
Dr. Sameer H. Sawant, SIOP

4. Requirements:
1.Experimental Animals: Frog
2.Equipments: Frog's board, dissecting instruments, pithing
needle, needle with thread, syringe with needle.
3.Drug & Solutions: Magnesium Sulphate 27% (Hypertonic)
Saline 0.9% made up to 0.45% (Hypotonic) Frog's Ringer
(Isotonic)
Dr. Sameer H. Sawant, SIOP

5. Theory: Saline Purgatives
• These are the salts comprising of highly charged ions and do
not cross the membrane freely
• They remain inside the lumen and retain the water through
osmotic forces
• They increase the volume of the content of the bowel
• Stretch the colon
• produce the normal stimulus for the contraction of the
muscles that leads to defecation
Dr. Sameer H. Sawant, SIOP

6. Some commonly used salts
1. Magnesium sulphate (Epsom salts)
2. Magnesium hydroxide (Milk of Magnesia)
3. Sodium sulphate (Glauber salt)
4. Potassium sodium tartarate
Dr. Sameer H. Sawant, SIOP

7. Procedure:
1. Pith a frog.
2. Expose the abdominal cavity.
3. Trace the small intestine and make three compartments by tying threads at
equal distance.
4. Secure the threads tightly so that no fluid can seep through from one
compartment to the other.
5. In the first compartment, inject 0.2ml of hypotonic saline, 0.2ml of
magnesium sulphate in the second compartment, and 0.2ml of Frog's
Ringer in the third compartment.
6. Wait for 20 minutes and record the observation.
Dr. Sameer H. Sawant, SIOP

8. Observation and Conclusion :
• Hypotonic solution causes the fluid to move from lumen into
circulation by process osmosis thereby shrinks the tissue
• Hypertonic solution moves the fluid from cells into the lumen
and swells the tissue
• Isotonic solution did not shows any fluid movement across the
intestinal membrane.
Dr. Sameer H. Sawant, SIOP

9. Dr. Sameer H. Sawant, SIOP

10. Observation Table
Compartment Compartment Effect
First Compartment : 0.2ml of
saline (hypotonic)
1 Shrunken
Second Compartment : 0.2ml
of Magnesium sulphate
(Hypertonic)
2 Swollen
Third Compartment: 0.2ml of
frog's ringer (Isotonic)
3 No Change
Dr. Sameer H. Sawant, SIOP