Angela Tabosa

Serotonin involvement in the electroacupuncture- and moxibustion-induced gastric emptying in rats

OBJECTIVE Electroacupuncture (EA) as well as moxibustion stimulation has been reported to produce an excitatory effect on the gastrointestinal motility of the rat. Serotonergic neurons of the mioenteric and submucous plexus are major participants in the gastrointestinal physiology. Here, we compared the outcomes of the stimulation of a specific set of acupoints with either acupuncture or moxibustion on the gastrointestinal motility and the role of serotonin (5-HT) in this effect. METHODS To analyze the role of 5-HT on the gastrointestinal motility of the rat, we studied the flow of 25 glass beads administered to the stomach, after treatment of the animals with a serotonin inhibitor (para-chlorophenylalanine [pCPA]). Acupuncture stimulation was performed on acupoints St-36 (Zusanli) and Sp-6 (Sanyinjiao), with electrical stimulation, or on acupoints Ren-10 (Xiawan), Ren-12 (Zhongwan) and St-25 (Tianshu), with moxibustion. Animals subjected to sham stimulation were used as controls in addition to naive, unstimulated animals. RESULTS Stimulation of the hind limb (St-36 and Sp-6) and abdominal (Ren-10, Ren-12, St-25) acupoints resulted in effective gastric emptying, as compared with sham-stimulated animals. Pretreatment of animals with pCPA abolished either the response provided by acupuncture stimulation in animal groups subjected to hind limb acupoints or the response provided by moxibustion stimulation in abdominal acupoints. CONCLUSION Our data suggest that moxibustion in the abdominal points and EA in the hind limb require an intact serotonergic pathway. In addition, we suggest that this involvement of serotonin is a general feature of the mediated effects of acupuncture on gastric emptying of the rat.

A Comparative Study of the Effects of Electroacupuncture and Moxibustion in the Gastrointestinal Motility of the Rat

We compared the outcomes of the stimulation of specific sets of acupoints with either acupuncture or moxibustion over peristalsis. Twenty-five plastic beads were orally administered in the stomach of the rats and 90 min later animals were sacrificed, the stomach and small intestine were opened, and the number of beads remaining in each segment was counted. Forty rats were immobilized for 20 min and stimulated at either abdominal or hindlimbs acupoints, with either electroacupuncture or moxibustion. Under this restraint (stress) condition electroacupuncture at hindlimb points or moxibustion at abdominal points significantly enhanced gastric emptying (P < 0.02) as well as intestinal motility compared with animals subjected only to immobilization and not stimulated with electroacupuncture or moxibustion. We conclude that the effects of different acupoints and modes of stimulation (electrical vs. moxibustion) over gastrointestinal motility in rats subjected to restraint-induced stress is not uniform and discuss the different neural pathways underlying these differences.

Electroacupuncture prevents cognitive deficits in pilocarpine-epileptic rats

Here we investigated the effects of electroacupuncture over the cognitive deficits in the pilocarpine model of epilepsy in rats. Acupuncture stimulation was provided at acupoints located in either the midline of the back and of the head [HD]: Gv-20 (Baihui), Gv-14 (Dazhui), Gv-2 (Yaoshu) and M-HN-3 (Yin Tang); or acupoints located in the limbs [LB]: St-36 (Zusanli) and Sp-6 (Sanyinjiao). In the elevated T-maze test, electroacupuncture at HD and LB acupoints produced an improvement in the acquisition and retention parameters. Retention in the inhibitory avoidance test was seen only in short-term retention and only for animals stimulated at HD. At histology it was found that electroacupuncture at HD acupoints abolished tissue shrinkage in dorsal hippocampus, basolateral nucleus of the amygdala, substantia nigra and perirhinal cortex, whereas stimulation of LB acupoints prevented tissue shrinkage in all of the above structures except dorsal hippocampus. Administration of p-chlorophenylalanine, a serotonergic releaser, abolished both behavioral and part of the histological changes in these animals. We conclude that electroacupuncture at HD and LB acupoints prevents atrophy of some limbic structures and improves cognitive deficits in pilocarpine-epileptic rats and that this effect is dependent on the serotonergic system.

Effect of the acupoints ST-36 (Zusanli) and SP-6 (Sanyinjiao) on intestinal myoelectric activity of Wistar rats

Despite its ancient use as a therapeutic tool to treat several ailments, acupuncture still faces the challenge of scrutiny by Western science both in terms of its efficacy and in terms of the characterization of its effects and mechanisms of actions underlying these effects. We investigated under well-controlled and carefully characterized conditions the influence of electrical stimulation of acupuncture points ST-36 (Zusanli) and SP-6 (Sanyinjiao) on the myoelectric activity of the small intestine of 38 adult male Wistar rats. Electrical recordings obtained by means of four electrodes chronically implanted in the small intestine were used to assess the effects of acupuncture (electroacupuncture stimulation set at 2 Hz, intermittent stimulation, 1 V, for 30 min). Immobilization of the animals was associated with a consistent decrease (-8 +/- 7%) in the myoelectric activity of the small intestine as measured by means of the root mean square. Conversely, acupuncture was able to significantly increase (overshoot) this activity compared to baseline (+44 +/- 7%). In contrast, immobilized animals subjected to sham acupuncture had only modest (nonsignificant) increases in myoelectric activity (+9 +/- 6%). Using carefully controlled conditions we confirmed previous noncontrolled studies on the ability of acupuncture to alter intestinal motility. The characterization of the topographic and temporal profiles of the effects observed here represents a basis for future dissection of the physiological and pharmacological systems underlying these effects.

Effect of moxibustion at acupoints Ren-12 (Zhongwan), St-25 (Tianshu), and St-36 (Zuzanli) in the prevention of gastric lesions induced by indomethacin in Wistar rats.

This study was aimed at assessing the physical characteristics underlying the action of moxibustion at acupoints Ren-12 (Zhongwan), St-25 (Tianshu), and St-36 (Zuzanli) in preventing acute injuries of the gastric mucous membrane induced by indomethacin in Wistar rats. Induction of gastric lesions, by means of intragastric administration of indomethacin (100 mg/kg), in adult male Wistar rats was followed by treatment with moxibustion using Artemisia vulgaris dried leaves at 60 or 45∘C, heating with Artemisia vulgaris charcoal at 50∘C, heating with a regular tobacco cigar at 50∘C, and heating with a regular water pad at 50∘C, The effects of the different heating protocols over the gastric lesions were then compared. In addition, another group of animals was pretreated with capsaicin (100 mg/kg, s.c.), in order to lesion C fibers and, 15 days later, subjected to indomethacin administration and moxibustion treatment. Moxibustion was significantly more efficient at 60∘C than at 45∘C in preventing gastric lesions triggered by indomethacin. Moxibustion applied in acupoints provided a significant reduction of the lesion area, which was two times less than that of animals stimulated in a nonacupoint (sham group). Comparing the therapeutic effects provided by different forms of heating over the gastric lesions, the burning of dry leaves of Artemísia vulgaris was significantly more efficient in preventing gastric lesions than moxibustion made with Artemísia charcoal or tobacco (cigar) or by heating the animal with a water pad. Desensitization of the afferent sensory C fibers by capsaicin significantly diminished the ability of moxibustion to block the lesions in the gastric mucous membrane. Moxibustion can efficiently prevent indomethacin-induced gastric lesions in rats and this effect is dependent on the temperature, the material used for moxibustion, the use of acupuncture points, and the integrity of C fibers.

Electroacupuncture reverses ethanol-induced locomotor sensitization and subsequent pERK expression in mice

Extracellular signal-regulated kinase (ERK) plays a role in neuronal changes induced by repeated drug exposure. Given that electroacupuncture reverses locomotor sensitization induced by ethanol, we investigated whether this effect is parallel to ERK signalling. Mice received daily ethanol (2 g/kg i.p), for 21 d. Electroacupuncture was performed daily, during four (subsequent) days of ethanol withdrawal. The stimulus of 2 Hz or 100 Hz was provided in combinations of two acupoints: Ea1 (ST-36/Zusanli and PC-6/Neiguan) or Ea2 (Du-14/Dazhui and Du-20/Baihui). The specificity of acupoint effects were assessed by the inclusion of additional groups: Ea3 (ST-25/Tianshu--acupoint used for other non-related disorders), Sham1 or Sham2 (transdermic stimulation near the respective acupoints). The control group was only handled during withdrawal and the saline group was chronically treated with saline and handled similarly to controls. At day 5 of withdrawal, each group was divided in two subgroups, according to the presence or absence of ethanol challenge. The animals were perfused and their brains processed for pERK immunohistochemistry. Only Ea1 at 100 Hz (Ea1_100) and Ea2 at 2 Hz (Ea2_2) reversed locomotor sensitization induced by ethanol. Ethanol withdrawal decreases pERK in the dorsomedial striatum. This decrease is not abolished by electroacupuncture. Conversely, ethanol challenge increases pERK in the dorsomedial striatum, infralimbic cortex and central nucleus of amygdala. The specificity of acupoint stimulation to reverse these increases was seen only for Ea2_2, in the infralimbic cortex and dorsomedial striatum. Therefore, behavioural effects of Ea2_2 (but not Ea1_100) depend, at least in part, on ERK signalling.

Electroacupuncture Inhibits Ethanol‐Induced Locomotor Sensitization and Alters homer1A mRNA Expression in Mice

BACKGROUND Here we investigated the effects of electroacupuncture over locomotor sensitization induced by ethanol in mice. METHODS Adult male Swiss mice were daily injected with ethanol (2 g/kg, i.p.) or saline for 21 days (acquisition phase). After 4 days of withdrawal, all animals were challenged with ethanol (1.4 g/kg, i.p.). The locomotor activity during 30 minutes was accessed just after the ethanol challenge. Electroacupuncture at acquisition, expression, or maintenance phases of locomotor sensitization was provided over ST-36 (Zusanli) or PC-6 (Neiguan) as well as concomitantly over these 2 acupoints. One hour after the challenge with ethanol, the animals were decapitated, the hippocampus, striatum, and prefrontal cortex were dissected, and the expression of homer1A mRNA assessed by PCR. RESULTS Electroacupuncture provided simultaneously over ST-36 and PC-6 (but not to ST-36 or PC-6 alone) inhibited the acquisition, expression, and maintenance of ethanol-induced locomotor sensitization. In addition, electroacupuncture blocked the diminution of homer1A mRNA expression triggered by ethanol in the acquisition (striatum and prefrontal cortex), expression (hippocampus), and in the maintenance (hippocampus and prefrontal cortex) phases. CONCLUSION Electroacupuncture provided concomitantly over ST-36 and PC-6 prevents the sensitization of the mesocorticolimbic pathway induced by ethanol in mice. In addition, these effects were accompanied by changes in the expression of homer1A. We suggest that electroacupuncture effects over ethanol-induced locomotor sensitization are associated to its ability to modulate homer1A expression and glutamatergic plasticity.

Effect of Eletroacupuncture on DU-14 (Dazhui), DU-2 (Yaoshu), and Liv-13 (Zhangmen) on the Survival of Wistar Rats' Dorsal Skin Flaps

The survival of skin flaps has great interest in many areas of Medicine. In practice, one of the most important complications in the use of skin flaps is the tissue ischemia, which frequently results in widespread necrosis and failure of the proposed treatments. The objective of this study was to evaluate the possible benefits of eletroacupuncture stimulation of the points DU-14 (Dazhui), DU-2 (Yaoshu), and Liv-13 (Zhangmen) over the skin flap survival of Wistar rats after 8 days of treatment. Forty male Wistar rats were allocated into four groups with 10 animals each. They were submitted to a surgical procedure in which a dorsal skin flap measuring 10 × 4 cm was elevated and then sutured back with a plastic barrier between the flap and the donor site. During the following 8 days, one group received electro stimulation in two “nonaccupoints” whereas the other one had the accupoints DU-14 (Dazhui), DU-2 (Yaoshu), and Liv-13 (Zhangmen) stimulated. After this period, the rats were killed and flaps were appraised qualitative and quantitatively. Data were evaluated with analysis of variance and to establish significance Fishers PLSD test was used when analysis of variance showed P < .05. It was observed that electroacupuncture group presented a skin flap survival index remarkably larger than the others. It has also shown a better evolution during the 8 days PO, confirmed by the lowest rate of necrosis and absent area. In this experimental model, eletroacupuncture was an efficient method to preserve vitality and decrease dorsal skin flap necrosis on Wistar rats.

Electroacupuncture inhibits CB1 upregulation induced by ethanol withdrawal in mice

CB1R play a role in alcohol withdrawal and in some effects of acupuncture. Interestingly, acupuncture has been used to alleviate alcohol withdrawal. Here, we investigated electroacupuncture (EA) effects during ethanol withdrawal on CB1R immunoreactivity. Male Swiss mice were daily injected with ethanol (2g/kg, i.p) (EtOH group), for 21 days. EA was performed daily during 4 days of ethanol withdrawal. The stimuli of 2 or 100 Hz were provided in two acupoints combination: Ea1 [(ST-36/Zusanli) and (PC-6/Neiguan)] or Ea2 [(DU-14/Dazhui) and (DU-20/Baihui)]. The specificity of the acupoints were assessed by the inclusion of three additional groups, Ea3 [(ST 25/Tianshu - acupoints used to other non-related disorders)], Sham1 and Sham2 (transdermic stimulation nearly to the respective acupoints). EtOH group were only handled during withdrawal and Saline group was chronically treated with Saline and handled similarly to EtOH group. One day after withdrawal the animals were perfused and their brains processed for immunohistochemistry. There was an increase of CB1R in the prefrontal cortex, striatum, hippocampus, amygdala and ventral tegmental area. The procedures used in the 2HzEa1 and 100HzEa2 groups were the most effective and specific to inhibit this CB1R upregulation. Therefore, EA inhibits CB1R upregulation seen in ethanol withdrawn mice. The specificity of acupoints stimulation depends of the encephalic nuclei, acupoints association and frequency of stimulation.

Short-term effect of acupuncture on intraocular pressure in healthy subjects

Purpose To evaluate the short-term effect of acupuncture on the intraocular pressure (IOP) in healthy subjects. Methods A randomised controlled double-blinded trial was performed. 48 healthy volunteers (94 eyes) were randomly allocated to three groups: acupuncture group—19 subjects (38 eyes) were submitted to a 20 min session of acupuncture (GB1, GB14 and BL1); sham group—14 subjects (27 eyes) were submitted to a 20 min session of acupuncture with needles inserted in false points; and control group—15 subjects (29 eyes) who underwent no intervention. All subjects had the IOP measured by a masked investigator using Goldmann applanation tonometry immediately before intervention, as well as 20 min and 24 h after. Results The mean (SD) IOP in the acupuncture group was 17.9 (3.3) mm Hg at baseline, 16.4 (3.9) mm Hg at 20 min and 16.3 (3.3) mm Hg at 24 h. The mean (SD) IOP in the sham group was 18.6 (3.3) mm Hg at baseline, 17.7 (2.6) mm Hg at 20 min and 15.9 (3.6) mm Hg at 24 h. The mean (SD) IOP in the control group was 16.9 (3.5) mm Hg at baseline, 16.5 (3.8) mm Hg at 20 min and 15.8 (3.3) mm Hg at 24 h. There was no statistically significant difference in the IOP variation (post-intervention minus baseline measurements) between groups after 20 min (p=0.13) and 24 h (p=0.21). Conclusion Acupuncture in the studied points did not produce significant short-term effect on the IOP of healthy individuals in comparison with control groups. Clinical Trials Registration Number: NCT00639977