Description A skin electrode made of conductant rubber 24 mm in diameter was fixed with EEG gel to the dorsum of one (randomly selected) hand, on the radial aspects of the middle of the second metacarpal bones, corresponding to the acupoint Hegu or LI 4, while another electrode was fixed onto the palmar surface opposite to the Hegu point to complete a circuit. Another pair of electrodes was attached onto the ipsilateral leg, one 2-3 cm lateral and 2-3 cm below the anterior tubercle of the tibia, corresponding to the Zusanli point or ST 36, and the other on the belly directly below the gastrocnemius muscle corresponding to the Chengshan point or UB 57.
Experimental Description
Transcutaneous nerve stimulation (TENS) treatment was given for 30 min to 37 patients divided into 3 groups of 10 patients and 1 group of 7 patients. Two groups received low-frequency (2 Hz) and the other 2 groups high-frequency (100 Hz) stimulation.
Sample Count
37
Age
21-62
Experiment
2Hz for MEAP (n=10);2Hz for Dyn A(n=7);100Hz for MEAP(n=10);100Hz for Dyn A(n=10)
Indicator
Immunoreactive opioid peptidesMet-enkephalin-Arg-Phe(MEAP)Dynorphin A(Dyn A)
Stimulation Method
TENS
Induction Method
Electroacupuncture Instrument Model
Manufacturer
Frequency
Waveform
Strength
Induction Time
WQ 1002
-
2/100 Hz
bidirectional square wave
26-30 mA
30 min
Acupuncture_Needle
Needle_Manufacturer
Needle_Depth
-
-
-
Description The 2 pairs of electrodes were connected to the dual channel electronic stimulator HAN ACUTENS model WQ 1002 which delivers bidirec- tional square waves of 0.3 msec duration, such that 1 positive wave was followed by 1 negative wave of identical intensity. The frequency was set at 2 Hz or 100 Hz. The amplitude was manually adjusted to en- sure a visible contraction of the underlying muscle, giving a current of 26-30 mA. The doctor doing these adjustments was blinded as to the clinical status of the patients or to the potential outcome of the chemical measurements. After the cessation of the 30 min stimulation period, a second sample of CSF was taken.
Anesthesia Method
AA
Clinical Trial Type
random
Effector
Low frequency TENS applied on the hand and the leg resulted in a marked increase (367%, P < 0.05) of ir-MEAP but not ir-Dyn A, whereas high-frequency (100 Hz) TENS produced a 49% increase in ir-Dyn A (P < 0.01) but not ir-MEAP. This is the first report in humans that 2 Hz and 100 Hz peripheral stimulation induces differential release of peptides from preproenkephalin and preprodynorphin, respectively.
Effect of low- and high-frequency TENS on Met-enkephalin-Arg-Phe and dynorphin A immunoreactivity in human lumbar CSF.
Abstract
Transcutaneous nerve stimulation (TENS) treatment was given for 30 min to 37 patients divided into 3 groups of 10 patients and 1 group of 7 patients. Two groups received low-frequency (2 Hz) and the other 2 groups high-frequency (100 Hz) stimulation. A diagnostic lumbar cerebrospinal fluid (CSF) sample was obtained immediately before and after stimulation. The CSF samples were subjected to analysis of immunoreactive (ir) opioid peptides, Met-enkephalin-Arg-Phe (MEAP) from preproenkephalin and dynorphin A (Dyn A) from preprodynorphin, respectively. Low frequency TENS applied on the hand and the leg resulted in a marked increase (367%, P less than 0.05) of ir-MEAP but not ir-Dyn A, whereas high-frequency (100 Hz) TENS produced a 49% increase in ir-Dyn A (P less than 0.01) but not ir-MEAP. This is the first report in humans that 2 Hz and 100 Hz peripheral stimulation induces differential release of peptides from preproenkephalin and preprodynorphin, respectively."
