[Show abstract][Hide abstract] ABSTRACT: The nucleus of the solitary tract (nucleus tractus solitarii; NTS) is a primary center for both visceral afferents and somatic afferents. Previous experiments have demonstrated that the NTS is closely connected to the stomach and acupoints in the Yangming Stomach Meridian of Foot (ST Meridian). In this study, extracellular recording and immunochemistry methods were used to analyze the discharge of neurons and c-Fos protein expression in the NTS following acupuncture at different acupoints and a nonacupoint. A total of 104 discharging neurons were detected in the NTS of 52 rats, of which 86 provided complete data. After acupuncture at Sibai (ST 2), Zusanli (ST 36), Neiting (ST 44), Quanliao (SI 18), and the nonacupoint, the neuron response rate in the NTS was 65.12%, 51.16%, 46.51%, 34.88% and 31.40% respectively. For neuron response rate, there was a significant difference among Sibai (ST 2), Zusanli (ST 36), Neiting (ST 44), Quanliao (SI 18), and the nonacupoint (p<0.01 or p<0.05). In the other 48 rats, the number of c-Fos immunoreactive neurons in the NTS by electroacupuncture (EA) at Sibai (ST 2) group was significantly higher than that EA at other acupoints and the nonacupoint (p<0.05 or p<0.01). EA at both Zusanli (ST 36) and Neiting (ST 44) increased c-Fos immunoreactive neurons significantly over EA at Quanliao (SI 18) and the nonacupoint (p<0.05 or p<0.01), while there was no difference between EA at Quanliao (SI 18) and the nonacupoint group (p>0.05). The experiments demonstrated that the afferent convergence in NTS are different by body surface points stimulus, which suggests that the NTS might be a primary center in the central nervous system receiving acupoints stimulus from the ST Meridian.
[Show abstract][Hide abstract] ABSTRACT: To explore the mechanism of the exciting effects of electro-acupuncture (EA) at Sibai on the gastric myoelectric activities.
A total of 32 rats were randomly divided into four groups. Through intraperitoneal injection with atropine (the anti-cholinergic agent by blockade of muscarinic receptors), hexamethonium (automatic nerve ganglion-blocking agent) and reserpine (anti-adrenergic agent by depleting the adrenergic nerve terminal of its norepinephrine store), effects of EA at Sibai on the gastric myoelectric activities of the denervated rats were observed.
After intraperitoneal injection of atropine and hexamethonium, the average amplitude and ratio of period to time in the phase of high activity of gastric myoelectric slow wave, and the average numbers of the peaks of gastric myoelectric fast wave were significantly decreased (P<0.01, P<0.05, P<0.01), while after intraperitoneal injection of reserpine, the aforementioned three parameters were increased (P<0.01, P<0.05, P<0.01). EA at Sibai point partially relieved the inhibitory effect of atropine and hexamethonium on the gastric myoelectric activities in the rats (P<0.05 or P>0.05).
Cholinergic and adrenergic nervous systems and autonomic nerve ganglion participate in the peripheral passage of the controlling effects of EA at Foot Yangming Channel on gastrointestinal tract.
World Journal of Gastroenterology 09/2006; 12(36):5897-901. · 2.37 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Clinical practice has shown that acupuncture at facial acupoints has curative effects on some visceral diseases (especially gastrointestinal diseases). However, the physiological basis has not been clarified yet. In the present study, expression of c-fos in the nucleus of the solitary tract (NTS) of rats following gastric distension and electroacupuncture (EA) at Yangbai (GB14) and Sibai (ST2) as well as Jiache (ST6) acupoints was observed by using immunohistochemistry technique. After EA at the three facial acupoints, c-fos immunoreactive (c-fos-IR) neurons were mainly distributed in the medial (mNTS) and intermediate subnucleus of the NTS, and a few were scatteredly distributed in the dorsalmedial and commissural subnucleus of the NTS. Furthermore, there is difference in the number of c-fos-IR neurons in the mNTS following EA at the three facial acupoints. The number in the EA at ST2 and GB14 group is the highest and the lowest, respectively. Gastric distension induces obviously the expression of c-fos, which is mainly confined in the mNTS. The results suggest that the noxious visceral and somatic afferent information from the stomach and face may converge in the mNTS, which may be involved in the effect of EA at facial acupoints on the gastrointestinal pain.
[Show abstract][Hide abstract] ABSTRACT: Acupuncture has been widely applied to treat gastrointestinal diseases in the clinic. However, its precise mechanism remains unknown. In the present study, effects of electroacupuncture (EA) at Zusanli acupoints (ST36) on gastric myoelectric activity and substance P (SP) in the dorsal vagal complex (DVC) were observed. EA at ST36 significantly increased the frequency of slow waves and the frequency of the spike potentials superimposed on the slow waves, which persisted for 90 min after cessation of EA and was completely abolished after bilateral vagotomy. Meanwhile, the mean optical density of SP immunoreactive fibers in the DVC increased following EA. The results suggested that EA at ST36 promoted the gastric myoelectric activity, which was regulated by the vagus, and SP in the DVC may be involved in the excitatory effects. Furthermore, EA had a relative long-term post-effect. We presumed that DVC may be a supraspinal center in the effect of EA on gastric function.