内关是手厥阴心包经的络穴

是针灸临床最常用的穴位之一。古人对内关的主治作用有许多描述。近年来的研究表明

针刺内关对冠心病心绞痛等多种疾患

具有明确的疗效

可使患者的心电图和左心功能等有所改善。实验资料表明

电针犬“内Twenty-five adult cats of either sex

weighing 1.8-2.7kg

were anesthetized intraperitioneally pentobarbital natriuum(30mg/kg)

and performed trachea cannula.The animals were immobilized by flaxedil and artificial respi- ration was maintained in the course of the experiment. “The median

ulnar and radial nerves were isolated about 3 cm above wrist joint of left forelimb of the cat.A laminectomy was performed on a sterotaxic apparatus to expose the C_3-T_3 segments of the spinal cord. stimulation of electrical pulse for the above-mentioned nerves and acu point“Neiguan”

was given by the electrical stimulator SEN-3101(intensity 5-6.2v

duration 0.01 ms)through isolator

controled by Singnal Processor 7SO6A

Evoked potentials of the dorsal root were recorded from C_3 to T_3 segment

and averaged 32 times for all the recording. 1)The compound action potentials

consisting of two negative potentials (group Ⅱ

Ⅲ)might be recorded in the dorsal roots of spinal cord of the ca- t by stimulus of the median

ulnar radial nerves. The afferent projective range were concentrated at C_4-T_1 segments of the spinal cord by stimulus the medianus nerve in 16 cats but the largest re- sponge area was C_5-C_7.Stimulating the ulnar in 14 cats

the largest respo- nse area was mainly distributed at C_7-C_8 segment.The afferent impulses was mainly projected to the C_4-T_1 spinal cord segments by stimulation of the radial nerves of 14 cats. 2)Evoked potential of the fibers of group Ⅱ

Ⅲ at dorsal roots of the spinal cord might be also recorded by electric stimuli the acupoint“Neiguan” (25 animals).Its main projective range was of the C_4-T_1 segments of spinal cord but the largest projective ranged from C_5 to C_6 segment

and C_6-C_7 as the main segments. 3)When the median nerve had been cut at the level of brachialplexus in 14 cats

of them

two cases potentials of the dorsal roots disappeared by stimulating“Neiguanu”.when the median and ulnar nerves had been cut simulta- neously

evoked potentials of eight cases did not be recorded.After cutting all three nerves

no evoked potential might be record in any case by stimulation “Neiguan” The largest potential amplitude of the dorsal roots was decreased 57.36±9. 77%

after cutting median nerve

and decreased 29.86±8.46% after only cu- tting ulnar and so redial nerve did

decreased 12.79±6.2%. The above result showed that the median

ulnar and radial nerves were the composition part of the signal afferent pathways by electric stimulation of acupoint“Neiguan”. Among them

median nerve might play an important role in this action

the next was the ulnar nerve and the radial had an effect in a certain extent

too.