In order to further investigate the analgesic effect of emitted qi of qigong and its mechanism, in this study, the influence of emitted qi on human skin pain threshold which was measured by the method of potassium mediated pain, the influence of emitted qi on the cortical evoked potentials elicited by c-fiber inputs (C-CEP as an index of response of somatosensory cortex t slow pain) in cat, and the role of endogenous opiate-like substances (OLS) in the analgesic effect of emitted qi were observed.
1. Influence of Emitted Qi on Human Skin Pain Threshold
Testees were divided into three groups: (1) emitted qi group, (2) imitating emitted qi group, and (3) control group.
In the first group, before emitted qi was delivered by a qigong master, the average value of skin pain threshold was 1525.4+-92.6uA (mean+-SE, n=11). But the average value was got up to 1631.1+-89.1uA 2.5-5 minutes after the delivery of emitted qi. Comparing this value with that before delivery of emitted qi difference was significant (P<0.05). The average value of pain threshold further rose to 1657.8+-93.3uA, 7-10 minutes after the delivery of emitted qi. Comparing this value with that before emitted qi, the difference was very significant (P<0.01). It was suggested that emitted qi could enhance the pain threshold obviously, indicating that emitted qi had analgesic effect.
In the second and third groups, the changes of skin pain threshold were not significant.
2. Influence of Emitted qi on The Response of Somatosensory Cortex to Slow Pain of Cat
(1) Influence of intravenous injection of morphine on C-CEP
The amplitudes of C-CEP were reduced by 45.3+-3.5%, 54.6+-4.6%, 46.7+-3.9%, 33.6+-2.3%, 16.0+-2.8% (mean+-SE, N=8, all the P<0.01) and 4.5+-6.2%(P>0.05), respectively, 3, 5, 8, 12, 16, and 22 minutes after morphine had been injected intravenously (2mg/kg). It was revealed that analgesic morphine had an obvious inhibitory effect on C-CEP, further showing that C-CEP might be a better index for the response of somatosensory cortex to slow pain.
(2) Influence of intracerebroventricular injection of naloxone upon the inhibition of morphine on C-CEP
The inhibition of morphine on C-CEP was decreased considerably 7 minutes after intracerebroventricular injection of naloxone (30ug/50ul). It was shown that naloxone could partially block the inhibition of morphine on C-CEP.
(3) Influence of Emitted Qi on C-CEP
The amplitudes of C-CEP were depressed by 36.9+-7.0%, 43.8+-8.8%, 41.0+-9.1%, and 41.5+-5.4%, respectively (all P<0.01), N=11), 3, 5, 10 and 15 minutes after the delivery of emitted qi. C-CEP recovered gradually after stopping the delivery of emitted qi. It was suggested that emitted qi could reduce the amplitude of C-CEP remarkably, indicating that emitted qi had an inhibitory effect on the response of somatosensory cortex to slow pain.
(4) Influence of intracerebroventricular injection of naloxone on the inhibition of somatosensory cortex to slow pain.
The inhibition of emitted qi on C-CEP was decreased significantly 7 minutes after intracerebroventricular injection of naloxone, showing that the inhibition of emitted qi might be related partially to release of endogenous opiate-like substances.
From the above results, it was suggested that emitted qi had obvious analgesic effect, raising human skin pain threshold and having an inhibitory effect which might be associated with release of endogenous opiate-like substances on the response of somatosensory cortex to slow pain.
