Effects and Mechanisms of Electroacupuncture at Zhongwan （CV12） on Gastric Nociceptive Response Induced by Gastric Acid Stimulation in Rats / 中医杂志

ObjectiveTo observe the effects of electroacupuncture at Zhongwan （CV12） on gastric nociceptive response induced by gastric acid stimulation and explore the underlying mechanisms associated with nuclei of the medullary viscerosensory and visceral motor neurons. MethodsTwenty SD rats were given intragastric administration of 0.5 mol/L diluted hydrochloric acid （0.5 ml/100 g） to induce gastric nociceptive response induction. Eight rats were randomly selected to record the gastric slow wave （GSW） area under the curve， and extracellular discharge frequency of neurons in the nucleus of the solitary tract （NTS） and dorsal motor nucleus of the vagus nerve （DMV） before intragastric administration and at 1， 5， 10， 15， 20， 25， 30， 35， 40， 45， 50， 55， and 60 minutes after intragastric administration. The remaining 12 rats received electroacupuncture intervention at Zhongwan within 5 to 25 minutes after intragastric administration of diluted hydrochloric acid， with a duration of one minute. The GSW area under the curve and extracellular discharge frequency of NTS and DMV neurons were compared between the 1-minute intervals before and after electroacupuncture intervention. ResultsCompared to the baseline before intragastric administration， the area under the curve of GSW significantly increased at 1， 5， 10， 15， 20， and 25 minutes after intragastric administration， and the extracellular discharge frequency of excitatory neurons in the NTS （accounting for 90%， 57/63） significantly increased at 1， 5， 10， 15， 20， 25， 30， 35， and 40 minutes， both reaching peak values at 1 minute after intragastric administration （P＜0.01 or P＜0.05）. The extracellular discharge frequency of inhibitory neurons in the DMV （accounting for 91%， 20/22） showed a non-significant increase at 1 minute after intragastric administration （P＞0.05）， but significantly decreased at other timepoints （P＜0.05）. Compared to the baseline before electroacupuncture intervention， the GSW area under the curve and the extracellular discharge frequency of excitatory neurons in the NTS significantly decreased （P＜0.05）， while the extracellular discharge frequency of inhibitory neurons in the DMV showed no significant difference （P＞0.05）. ConclusionElectroacupuncture at Zhongwan can improve gastric nociceptive response induced by gastric acid stimulation， possibly by reducing the transmission of visceral sensation and decreasing the excitability of NTS neurons in the medulla.

Effects of vagus nerve stimulation on inflammatory factors and apoptosis in depression model rats / 中华行为医学与脑科学杂志

Objective To explore the influence of vagus nerve stimulation (VNS) on inflammatory factors in serum and nucleus of the solitary tract,and hippocampal apoptosis in rats with depression induced by chronic unpredictable stress ( CUS). Methods Totally 32 male Sprague Dawley ( SD) rats aged 8-9 weeks were selected. Eight rats were chosen as control group,and the other 24 rats were treated as the de-pression model with CUS. The rats were randomly divided into CUS,fluoxetine and VNS group,with 8 rats in each group after successful modeling. The control group and CUS group were induced by normal saline. Flu-oxetine group and VNS group were implanted with VNS stimulation electrode. The VNS stimulation lasted for 28 d. On the time points of before experiment,after modeling and after treatment,the sucrose consumption test and open-field test (OFT) were performed to observe the behavioral changes of rats. Elisa was used to detect the levels of TNF-α,IL-6 and IL-1β in serum and nucleus of the solitary tract. Cell apoptosis was ob-served with TUNEL staining in hippocampal CA1 region. Results ( 1) Sucrose consumption experiment and OFT showed that,compared with the CUS group,the consumption of sucrose,percentage of sucrose con-sumption,scores of vertical and horizontal movement increased significantly in the VNS group ( consumption of sucrose: (11. 78±2. 67) ml,(8. 06±2. 85) ml; percentage of sucrose consumption: (72. 31±9. 98)%, (63. 67±8. 95)%; score of vertical movement: (16. 61±3. 98),(10. 31±3. 86); score of horizontal move-ment: (44. 25±9. 59),(36. 21±7. 21)) (t=4. 87,7. 98,5. 87,9. 12,all P<0. 05). There was no signifi-cant difference between VNS and fluoxetine groups (consumption of sucrose: (11. 32±2. 66) ml; percentage of sucrose consumption: (71. 31±9. 03)%; score of vertical movement: (15. 63±4. 11); score of horizontal movement: (45. 61±8. 54)) (t=-0. 32,-1. 83,0. 98,-1. 13,all P>0. 05). (2) Compared with the CUS group,levels of TNF-α,IL-6 and IL-1β in serum decreased in the VNS group ( serum TNF-α: ( 46. 72 ± 11. 63) pg/ml,(125. 47±15. 18) pg/ml; serum IL-6: (243. 65±38. 90) pg/ml,(441. 39±83. 31) pg/ml;serum IL-1β: (209. 31±32. 45) pg/ml,(339. 21±76. 37) pg/ml) (t=-70. 38,-196. 25,-131. 13,all P<0. 05). The results in the VNS group were lower than those in the fluoxetine group (serum TNF-α: (58. 76 ±12. 64) pg/ml; serum IL-6: (308. 83± 64. 31) pg /ml,serum IL-1β: ( 249. 18 ± 43. 6) pg/ml) ( t=-15. 38,-64. 25,-18. 83,both P<0. 05). The levels of TNF-α,IL-6 and IL-1β in nucleus of the solitary tract in the VNS group were lower than those in the CUS ( TNF-α: (53. 52± 12. 31) pg/ml,(135. 51± 20. 64)pg/ml; IL-6: (265. 31±45. 63) pg/ml,(465. 32±60. 21) pg/ml; IL-1β: (212. 66±43. 32)pg/ml, (365. 96±76. 32) pg/ml) (t=-79. 38,-189. 13,-127. 50,all P<0. 05) and fluoxetine groups (TNF-α:(63. 42±10. 64) pg/ml; IL-6: (315. 62±53. 21) pg/ml; IL-1β: (278. 32±65. 38) pg/ml ) (t=-10. 25,-39. 00,-83. 00,all P<0. 05). (3) The apoptotic rate of hippocampal CA1 region in VNS group ((21. 41± 5. 86)%) was lower than that in the CUS group ((32. 78±8. 32)%) (t=-10. 75,P<0. 05); and there was no difference between VNS group and fluoxetine group ((22. 54±6. 31)%) (t=-1. 75,P>0. 05). Conclu-sion VNS can improve the depression behavior in rats with depression induced by CUS and the mechanism maybe related to inhibiting the expression of TNF-α,IL-6 and IL-1β in serum and nucleus of the solitary tract and cell apoptosis in hippocampal CA1 region.

c-Fos-like Immunoreactivity in the nucleus of the solitary tract following taste stimulation of the contralateral side of the tongue / 동물의과학연구지

Taste receptors of the anterior tongue are innervated by the chorda tympani (CT) branch of the facial (VIIth) nerve. The CT nerve transmits information on taste to the ipsilateral nucleus of the solitary tract (NST), which is the first taste central nucleus in the medulla. Taste information is known to be transferred ipsilaterally along the taste pathway in the central nervous system. Some patients with unilateral CT damage often retain their ability to sense taste. This phenomenon is not explained by the unilateral taste pathway. We examined whether neurons in the NST receive information on taste from the contralateral side of the tongue by measuring c-Fos-like Immunoreactivity (cFLI) following taste stimulation of the contralateral side of the tongue in the anesthetized rats. We used four basic taste stimuli, 1.0 M sucrose, 0.3 M NaCl, 0.01 M citric acid, 0.03 M QHCl, and distilled water. Stimulation of one side of the tongue with taste stimuli induced cFLI in the NST bilaterally. The mean number of cFLI ranged from 23.28 +/- 2.46 by contralateral QHCl to 30.28 +/- 2.26 by ipsilateral NaCl stimulation. The difference between the number of cFLI in the ipsilaterl and contralateral NST was not significant. The result of the current study suggests that neurons in the NST receive information on taste not only from the ipsilateral but also the contralateral side of the tongue.

c-Fos Expression in the Nucleus of the Solitary Tract in Response to Salt Stimulation in Rats

Salt signals in tongue are relayed to the nucleus of the solitary tract (NST). This signaling is very important to determine whether to swallow salt-related nutrition or not and suggests some implications in discrimination of salt concentration. Salt concentration-dependent electrical responses in the chorda tympani and the NST were well reported. But salt concentration-dependency and spatial distribution of c-Fos in the NST were not well established. In the present study, NaCl signaling in the NST was studied in urethane-anesthetized rats. The c-Fos immunoreactivity in the six different NST areas along the rostral-caudal axis and six subregions in each of bilateral NST were compared between applications of distilled water and different concentrations of NaCl to the tongue of experimental animals. From this study, salt stimulation with high concentration (1.0 M NaCl) induced significantly higher c-Fos expression in intermediate NST and dorsal-medial and dorsal-middle subregions of the NST compared to distilled water stimulation. The result represents the specific spatial distribution of salt taste perception in the NST.

Changes in sodium appetite evoked by lesions of the commissural nucleus of the tractus solitarius

Ablation of the area postrema/caudal nucleus of the tractus solitarius (NTS) complex increases sodium intake, but the effect of selective lesions of the caudal NTS is not known. We measured depletion-induced sodium intake in rats with electrolytic lesions of the commissural NTS that spared the area postrema. One day after the lesion, rats were depleted of sodium with furosemide (10 mg/kg body weight, sc) and then had access to water and a sodium-deficient diet for 24 h when 1.8 percent NaCl was offered. Water and saline intakes were measured for 2 h. Saline intake was higher in lesioned than in sham-lesioned rats (mean ± SEM: 20 ± 2 vs 11 ± 3 mL/2 h, P < 0.05, N = 6-7). Saline intake remained elevated in lesioned rats when the tests were repeated 6 and 14 days after the lesion, and water intake in these two tests was increased as well. Water intake seemed to be secondary to saline intake both in lesioned and in sham-lesioned rats. A second group of rats was offered 10 percent sucrose for 2 h/day before and 2, 7, and 15 days after lesion. Sucrose intake in lesioned rats was higher than in sham-lesioned rats only 7 days after lesioning. A possible explanation for the increased saline intake in rats with commissural NTS lesions could be a reduced gastrointestinal feedback inhibition. The commissural NTS is probably part of a pathway for inhibitory control of sodium intake that also involves the area postrema and the parabrachial nucleus.

Treatment and Mechanism of Surface Electrical Stimulation for Severe Dysphagia Caused by Lower Brainstem Infarction / 中国康复理论与实践

@#Objective To study the potential mechanism of recovery from dysphagia after surface electrical stimulation. Methods 3 cases recovery from dysphagia caused by lower brainstem infarction after surface electrical stimulation of lower mandible and trigeminal nerves were analyzed. Results After 3～16 weeks surface electrical stimulation, the swallow assessment scores reached from 0 to 6 in all the 3 patients. Conclusion Surface electrical stimulation can facilitate the recovery of swallow function, which may be involved with the sensory input, especially the integration of nucleus of the solitary tract (NTS).

PROJECTION OF THE CALBINDIN D-28K NEURONS RECEIVING VISCERAL NOCICEPTIVE INFORMATION FROM INTERSTITIAL NUCLEUS OF THE SPINAL TRIGEMINAL TRACT TO NUCLEUS OF THE SOLITARY TRACT IN THE RAT / 解剖学报

Objective To investigate the calbindin D\|28K (CB) neurons that receive the visceral nociceptive information in the interstitial nucleus of the spinal trigeminal tract (INV) directly project to the nucleus of the solitary tract (NTS). Methods Triple\|labeled methods of fluorogold (FG) retrograde tracing combined with Fos and CB proteins immunofluorescence histochemistry after formalin stimulating upper alimentary tract. Results Most of FG\|retrograde labeled neurons distributed in the paratrigeminal nucleus (PaV) and the dorsal paramarginal nucleus (PaMd) of INV ipsilateral to the FG injection. About 71^2% of FG\|retrograde labeled neurons contained CB and 31^5% of FG/CB double\|labeled neurons exhibited positive Fos\|immunoreaction in INV.Conclusion The results suggested that a part of neurons containing CB in INV receive the visceral nociceptive information and directly project to NTS. CB neurons might play an important role in transmitting visceral nociceptive information from INV to NTS. [

THE PROJECTION OF THE NEURONS CONTAI-NING TYROSINE-HYDROXYLASE, NEUROTEN-SIN, CHOLECYSTOKININ IN THE NUCLEUSOF THE SOLITARY TRACT TO THE NUC-LEUS ACCUMBENS IN THE RAT——A STUDY BY HRP TRACING COMBINED WITH IMMUNOCYTOCHEMICAL TECHNIQUE / 解剖学报

The projection from the nucleus of solitary tract (Sol) to the nucleus accumbens (Acb) was examined by using HRP retrograde and anterograde tracing combined with immunocytochemical double-labeling technique. The following results were obtained: (1) when WGA-HRP was injected into the caudal part of the Sol, the labeled fibers, terminals and cell bodies were found in the ventromedial area of the caudal Acb. After injecting HRP into the ventromedial area of the caudal Acb, labeled cell bodies and terminals were found in the ipsilateral and contralateral caudal part of the Sol,mainly in the commissure nucleus and the medial subnucleus of nucleus of solitary tract. (2) After injecting HRP into the Acb and combined with immunocytochemical method, many HRP-TH, HRP-NT, and HRP-CCK double-labeled cell bodies were found in the caudal part of the Sol. The number of the HRP-TH double-labeled cell bodies was most numerous, HRP-NT cells was next and HRP-CCK cells was even less.

CONNECTIONS BETWEEN THE SPINAL CORD AND THE NUCLEUS OF THE SOLITARY TRACT IN THE RABBIT / 解剖学报

HRP or WGA-HRP was injected into the rabbit cervical, thoracic, or lumbar spinal gray unilaterally and the retrograde labeled ceils and anterograde labeled terminal branches in the nucleus of the solitary tract were studied. The labeled cells were found in the caudal part of the nucleus. The amount of the labeled cells in the cervical and thoracic injection cases out numbered that of the lumbar cases. In all the cases labeled ceils were most concentrated near the obex level, mainly located ventromedial to the tract. Some could be found ventral, ven- trolateral, lateral and medial to and in the vicinity of the tract. In the medial part of the nucleus labeled cells were limited in its ventral part dorsal to the dorsal motor nucleus of the vagus nerve. No labeling could be ascertained in the subnucleus parvocellularis. In the thoracic injection cases a group of labeled cells were discovered dorsolateral to the tract where only a few labeled ceils could be found in the cervical and lumbar cases. Labeled terminal branches largely accompanied the labeledcells. Thus the chance of establishing direct synaptic contact between spino-solitary fibers and the spinal projection cells of the nucleus of the solitary tract is great. At the level of obex a narrow band of terminal labeling along the dorsolateral border of the nucleus was identified. Except occasionally no labeled cells were found in this zone, an area probably related to cardiac function.