Effects of Acupuncture on Autonomic Nervous Functions During Sleep: Comparison with Nonacupuncture Site Stimulation Using a Crossover Design.

Objectives: Although many studies have shown that acupuncture can improve sleep quality, there is no clear evidence by objective physiological measures. The authors investigated the effects of acupuncture on the autonomic indices of heart rate variability (HRV) during sleep. Design: The authors applied true acupuncture and sham-site stimulations in 10 healthy adult males (mean ± standard deviation age, 40 ± 9 years) and compared autonomic nerve indices of HRV during each sleep stage in a crossover design. The sleep stages were estimated by the combined analysis of an HRV maker of non-rapid eye movement (REM) sleep (HRV sleep index [Hsi]) and actigraphic body movement. Results: Heart rate was lower (true vs. sham acupuncture, mean ± standard error of the mean, 60.9 ± 1.8 vs. 61.7 ± 1.7 bpm, p < 0.0001) and the power of low-frequency and high-frequency components of HRV was higher (35.6 ± 2.0 vs. 34.7 ± 2.0 msec, p = 0.04 and 26.7 ± 3.2 vs. 25.8 ± 3.2 msec, p < 0.0001, respectively) after the true acupuncture compared with the sham-site stimulation throughout sleep. During non-REM sleep, heart rate was lower (59.6 ± 1.8 vs. 60.1 ± 1.8 bpm, p = 0.0004) and the power of low-frequency and high-frequency components were higher (27.7 ± 1.8 vs. 26.1 ± 1.8 msec p = 0.0004 and 28.4 ± 3.5 vs. 27.7 ± 3.5 msec, p = 0.004) after the true acupuncture than the sham-site stimulation. Whereas during REM sleep, there was no significant difference in either HRV indices between them, while heart rate was lower after the true acupuncture than the sham-site stimulation (60.8 ± 1.6 vs. 61.7 ± 1.6 bpm, p < 0.0001). Conclusions: Acupuncture increases parasympathetic HRV indices during sleep, especially during the non-REM stage.

Effects of acupuncture stimulation on blood glucose concentration in the Otsuka Long-Evans Tokushima Fatty (OLETF) rat, an animal model for type-2 diabetes mellitus.

BACKGROUND: Effects of acupuncture stimulation on blood glucose concentration and body weight were investigated in the Otsuka Long-Evans Tokushima Fatty (OLETF) rat, a model for type-2 diabetes. MATERIAL AND METHODS: Three groups of rats were used: OLETF, acupuncture-treated OLETF (AcOLETF), and Long-Evans Tokushima Otsuka (LETO) rats (as control for the OLETF rats). In AcOLETF rats, acupuncture stimulation was applied twice a week to 6 points (zhongwan, tianshu, qihai, ganshu, pishu, shenshu) and changes in blood glucose concentration and body weight were measured. RESULTS: Initially, at 6 weeks old, there was no significant difference in blood glucose levels between groups. Blood glucose levels increased with age in each group, reaching a maximum of about 430 mg/dl at 37 weeks in OLETF rats. In AcOLETF rats, blood glucose levels increased at a slower rate than in OLETF rats, reaching a maximum concentration of about 280 mg/dl at 37 weeks of age, significantly lower than that in OLETF rats. The concentration of blood glucose in LETO rats had stabilized at a maximum value of 120~140 mg/dl by 16 weeks, remaining at this level for up to 39 weeks. In each group, body weight increased with age and was not affected by acupuncture treatment. CONCLUSIONS: In OLETF rats, acupuncture treatment significantly reduced blood glucose levels, but not their body weight, suggesting that acupuncture therapy was effective in preventing the development of type-2 diabetes mellitus.

Site-specific organ-selective effect of epifascial acupuncture on cardiac and gastric autonomic functions.

Needle stimulation at the specific sites of body surface modulates autonomic functions in various organs. To examine their site-specificity and organ-selectivity, the changes in electrogastrogram (EGG) and heart rate variability (HRV) with such stimulation at PC6 (forearm), BL20 (back), CV12 (abdomen), BL32 (sacral), and ST36 (lower leg) were analyzed in healthy men. Stimulation at CV12 increased vagal HRV component without affecting dominant EGG frequency. Conversely, stimulation at BL32 decreased dominant EGG frequency without affecting vagal HRV component. Stimulation at the other points affected neither of them. These support site-specific and organ-selective effect of body surface needle stimulation on autonomic functions.

Acupuncture to Danzhong but not to Zhongting increases the cardiac vagal component of heart rate variability.

There is currently no convincing evidence that acupuncture has any specific effects on autonomic nervous function as assessed by heart rate variability (HRV). We examined whether the stimulation of neighboring acupunctural points, Danzhong (CV17) and Zhongting (CV16) on the anterior median line of the thorax, induced different effects on HRV. In 14 healthy males, epifascial acupunctural stimulation (single instantaneous needle stimulation on the fascial surface without producing De-Qi sensation) was performed at CV17 and CV16 on different days in a clinical study utilizing a cross-over design. We found that the stimulation of CV17, but not of CV16, decreased the heart rate (P=0.01, repeated measures ANOVA) and increased the power of the high-frequency component of the HRV, an index of cardiac vagal activity (P=0.01). The low-frequency to high-frequency ratio, an index of sympathetic activity showed no significant changes for either point. Our observations could not be explained as either nonspecific or psychological/placebo effects of needle stimulation. This study provides strong evidence for the presence of a specific acupunctural point that causes the modulation of cardiac autonomic function.

The effects of bradykinin agonists and antagonists on visceral polymodal receptor activities.

The endogenous algesic agent bradykinin (BK) is a consistent stimulant for the polymodal receptor, a type of nociceptor. Two types of BK receptor, B1 and B2, have been proposed in smooth muscles by Regoli. The type of BK receptor mediating the BK response of the polymodal receptor was studied using 3 BK analogs, des-Arg9-BK (a B1 agonist), des-Arg9-[Leu8]-BK (a B1 antagonist), and [Thi5,8, D-Phe7]-BK (a B2 antagonist). Single- and multi-fiber activities from testicular polymodal receptors were recorded in vitro using testis-spermatic nerve preparations excised from dogs anesthetized with pentobarbital (30 mg/kg, i.v.). Neither des-Arg9-BK, des-Arg9-[Leu8]-BK, nor [Thi5,8,D-Phe7]-BK induced discharges in nociceptors at concentrations up to 9.4 x 10(-6) M. Des-Arg9-[Leu8]-BK (up to 9.4 x 10(-6) M) did not suppress responses to BK (9.4 x 10(-8 approximately -9) M), whereas [Thi5,8,D-Phe7]-BK (above 2.8 x 10(-7) M) suppressed the BK response in a concentration-dependent manner and shifted the concentration-response curve of BK to the right. It was ascertained that [Thi5,8,D-Phe7]-BK had no effect on responses to noxious heat and high K+ solution. These results suggest that the BK receptor mediating the nociceptor response to BK is of the B2 type.