Expression of galanin in rat primary sensory afferents after moxibustion to the skin

Characterizing heat-sensitization responses in suspended moxibustion with high-density EEG

OBJECTIVE

We have reported "heat-sensitization" responses during suspended moxibustion, whose occurrence is associated with significantly better therapeutic effects. The present study aimed to characterize the electrophysiological features of this interesting phenomenon with high-density electroencephalography (EEG).

METHODS

We performed EEG recording in a group of patients with chronic low back pain before, during, and after moxibustion treatment at DU3.

RESULTS

12 out of 25 subjects experienced strong heat-sensitization during moxibustion, which was accompanied by increased power spectral densities (PSDs) at the theta, alpha, and beta frequency bands. The scalp topographies of averaged power indicated that the theta and beta PSD changes were most obvious in fronto-central regions, whereas those of the alpha band were more global. In addition, nonsensitized and sensitized groups showed distinct activity patterns, with heat-sensitization inducing increased phase coherence at the theta and beta ranges.

CONCLUSIONS

These data were the first objective evidence of heat-sensitization responses during suspended moxibustion, which were characterized by widespread oscillatory changes in scalp EEG.

The Spatial and Segmental Innervation of Somatic Acupoint — A Study of Canine Shen-Shu Point (BL-23)

Although an acupuncture needle penetrates the skin, subcutaneous tissue, and underlying muscle, the most effective locus for the somatic acupoint on the needle path is not well established. We therefore investigated the sensory innervations of tissues in the needle path of the canine Shen-Shu point and evaluated their roles in initiating an acupunctural signal. Horseradish peroxidase solution was injected at all three levels within the acupoint. Only a few peroxidase-positive neurons were observed in the L1 dorsal root ganglion following intradermal injection. Following subcutaneous injection, peroxidase-labeled neurons were detected extending from spinal levels T10 to L2, with maximal labeling at T12 (46.3%). Approximately 95% of positive neurons were at spinal levels T11, T12, T13, and L1. As a result of an intramuscular injection, labeled neurons were observed at spinal levels T12 to L3, with most labeling occurring at L1 (39.9%). Approximately 95% of positive neurons were at spinal levels T13, L1, and L2. The results suggest that most afferent terminals are in the subcutaneous tissue rather than the muscular tissue, with an approximate ratio of 3.75:1. The data provide solid evidence that sensory innervation to a somatic acupoint is confined to a spinal segment and spatially organized, and we speculate that to cause a maximum effect, the centripetally transmitted signal from needling a somatic acupoint is spatio-segmental and divergently amplified.

Effect of Moxibustion on Dopaminergic and Serotonergic Systems of Rat Nucleus Accumbens

Acupuncture and moxibustion are traditional medical treatments that have come to play important roles in complementary and alternative medicines. Moxibustion also has a long history as a folk remedy in Japan, particularly due to the technical simplicity and selective efficacy on certain types of disease and distress. This study examined the effects of moxibustion focusing on the brain reward system, particularly in the nucleus accumbens. The effects of moxibustion stimulation at various sites and frequencies on monoamine levels of adult male Sprague-Dawley rats were examined using high-preformance liquid chromatography of dissected nucleus accumbens tissues. The rats weighing 290-310 g were divided into 3 groups according to the moxibustion point used: hindlimb, lumbar or parietal points. Each group was further divided into 3 subgroups, with stimulation for 10 consecutive days, for 1 day, or sham treatment (control). On each day of stimulation, 5 moxibustion cones with a peak temperature of 200 degrees C were applied consecutively. Stimulation of any point on 1 day only did not change dopamine or serotonin levels, but lumbar stimulation significantly increased the metabolic turnover of dopamine. Conversely, stimulation for 10 consecutive days resulted in significantly decreased serotonin levels for hindlimb and parietal stimulations, and significantly increased 5-hydroxyindolacetic acid/serotonin ratio for hindlimb stimulation. These results suggest that the metabolic turnover of serotonin release may be accentuated by moxibustion in a reward-related brain area. Moxibustion over consecutive days, especially that to peripheral regions, appears most efficient to influence on monoamine levels in the nucleus accumbens.

Galanin-immunoreactive cells and their relation to calcitonin gene-related peptide-, substance P- and somatostatin-immunoreactive cells in rat lumbar dorsal root ganglia

We report upon the distribution of galanin-immunoreactive (GAL-IR) cells in the lumbar dorsal root ganglia (DRG) of the rat, and upon the distribution of GAL-IR cells, which also contain calcitonin gene-related peptide (CGRP)-, substance P (SP)- and somatostatin (SOM)-immunoreactivity. Neuropeptide-immunoreactive lumbar DRG cells were 55.8% for CGRP, 12.7% for SP, and 6.5% for GAL in lumbar DRG cells. There was no significant difference between the right and left DRGs (L1-L6) for any neuropeptide-immunoreactive cell (P < 0.01). In terms of size distribution, CGRP-immunoreactive cells were identified below 1500 microm2, and SP-, and GAL-IR cells below 600 microm2. Neuropeptide immunoreactive cells showed various immunoreactivities in the cytoplasm according to each neuropeptide. CGRP and SP immunoreactive cells were colocalized with GAL immunoreactive cells in the serial sections about 83.3 and 60% respectively, but SOM colocalizing with GAL-IR cells were not in evidence. The current results confirm and extend previous results, and show that neuropeptides can coexist in single sensory neurones of the rat DRG. In addition, our results demonstrate that the normal distribution of some neurotransmitters modulating sensory action in Wistar Kyoto rat, make this model more prone to develop neuropathic pain than Sprague-Dawley rat.