Relationship Between Dorsal Horn Cell Activity and Electrical Stimulation of Peripheral Nerve with Special Reference of Stimulatory Parameters.
- Author:
Taick Sang NAM
1
;
Young Ho LEE
;
Youn Hi KIM
;
Kwang Se PAIK
Author Information
1. Department of Neurology, Phsiology University, Korea.
- Publication Type:Original Article
- MeSH:
Analgesia;
Animals;
Carbon;
Cats;
Electric Stimulation*;
Glass;
Microelectrodes;
Naloxone;
Nerve Fibers;
Nerve Fibers, Unmyelinated;
Neurons;
Peripheral Nerves*;
Peroneal Nerve;
Posterior Horn Cells*;
Punctures;
Spinal Cord;
Tibial Nerve;
Transcutaneous Electric Nerve Stimulation
- From:Journal of the Korean Neurological Association
1991;9(2):186-202
- CountryRepublic of Korea
- Language:Korean
-
Abstract:
Transcutaneous electrical nerve stimulation (TENS), acupuncture-needling, and electroacu! Puncture are useful non-ablative methods in medical practice for relief of acute and chronic r pain These procedures appear to work by causing an increased discharge in afferent nerve fibers which in turn modifies the transmission of impulses in pain pathways. The present study was performed to evaluate the analgesic effects of peripheral nerve stimulation with different stimulatory parameters in decerebrated cats and spinalized cats. And we studied the effects of naloxone, a specific opiate antagonist, on analgesia produced by 50 Hz, C intensity conditioning stimulation. The electrical response of.spinal neurons was elicited either by electrical stimulation of the ipsilateral common peroneal nerve or tibial nerve, and then the single unit activity of the dorsal horn cell was recorded with a carbon filament-filled glass microelectrode at the lumbosacral spinal cord. The conditioning stimuli which provoke the pain inhibitory mechanism were applied to the cornmon peroneal nerve or tibial nerve with a relatively high frequency (25, 50, 200Hz) for 15, 30, and 60 seconds at suprathreshold intensity for A delta or C fiber. The results of the experiment are summarized as follows: 1. Peripheral conditioning stimulation at C strength showed larger analgesic effects than those produced by stimulation at A delta strength. And analgesic effects produced by conditioning stimulation for 30sec were greater than those produced by stimulation for 15sec, but showed no statistically significant difference from those produced by stimulation for 60 sec. 2. Analgesic effects produced by 50Hz conditioning stimulation were greater than thoseproduced by 25Hz stimulation. But 200Hz stimulation showed a lesser analgesic effect than 50 or 25Hz conditioning stimulation. 3. The analgesic effect produced by 50Hz conditioning stimulation was only slightly affected by naloxone, a specific opiate antagonist, indicating that involvement of an endogenous opiate system was minimal. 4. The analgesic effect produced by conditioning stimulation in decerebrated cats was nearly the same as in spinal cats suggesting that the neural circuitry responsible for the analgesic action seems to reside mostly within the spinal cord. From the above results, it is concluded that 1) frequency of stimulation is important for an efficient analgesia, i.e., stimulation with excessively high frequency decreases the analgesic effect, 2) the analgesic effect produced by high frequency conditioning stimulation may be minimally mediated by an endogenous opiate system, and 3) the site of analgesic action resides mainly in the spinal cord.
