1. Li Jingxin Physiologcal Department
DEMONSTRATE THE GENESIS OF BIPHASIC POTENTIAL
Li Jingxin
Physiologcal Department

2. IMPORTANT QUESTIONS
1.what’s the action potential?
2.how to record it?

3. 1.Intracellular recording

5. 2.Extracellular recording

6. A B A B A B
Nerve fiber

7. How to prepare a sciatic nerve preparation.

8. Animal

9. PROCEDURE 1. PITHING
Pithing is done to destroy the brain and spinal cord by inserting the pithing needle

10. pithing needle
great foramen

11. 2.DISSECTION 1.remove the head and viscera from the body,
2.remove the skin from legs
3.with a pair of scissors the vertebral column is divided into two equal halves longitudinally, so that two preparations can be prepared.

12. 2.DISSECTION
4.With the help of glass dissecting needle,dissociate the sciatic nerve carefully along edge of the vertebral column,and then looking for the sciatic groove located between biceps femoris and semimembranous muscle, expose and Separate the sciatic nerve down to knee joint longitudinally along the groove and then separate the peroneal nerve located on the surface of gastrocnemius muscle. A thread is tied around the origin of sciatic nerve, cutting the nerve up the thread.Put it in the .shield trough.

13. the sciatic nerve and dissect it .
PRECAUTIONS
1. Keep the tissue moist throughout the experiment by dipping it in the Ringer's solution. 2. Do not touch the nerve with finger or a metallic instrument. Use a glass rod for tracing the course of
the sciatic nerve and dissect it .