scholarly journals Effects of Electrical Stimulation at Different Locations in the Central Nucleus of Amygdala on Gastric Motility and Spike Activity

2016 ◽  
pp. 693-700 ◽  
Author(s):  
F. HE ◽  
H.-B. AI
Keyword(s):  
Electrical Stimulation ◽  
Gastric Motility ◽  
Spike Activity ◽  
Central Nucleus ◽  
Motor Nucleus ◽  
Dorsal Vagal Complex ◽  
Motility Index ◽  
Medial Nucleus ◽  
Dorsal Motor Nucleus ◽  
Stimulation Of

The aim of the study was to determine the effects of electrical stimulation of different locations in the central nucleus of amygdala (CNA) on gastric motility and spike activity in dorsal vagal complex. Gastric motility index (GMI) and firing rate (FR) of dorsal vagal complex neurons were measured in adult Wistar rats respectively. Neuronal spikes in dorsal vagal complex (DVC) were recorded extracellularly with single-barrel glass microelectrodes. Each type of responses elicited by electrical stimulation in medial (CEM) and lateral (CEL) subdivisions of CNA were recorded, respectively. GMI was significantly increased after stimulation of CEM (p<0.01), and significantly decreased in response to CEL stimulation (p<0.01). After stimulation of CEM, FR in medial nucleus of the solitary tract (mNST) decreased by 31.6 % (p<0.01) and that in dorsal motor nucleus of the vagus (DMNV) increased by 27.1 % (p<0.01). On the contrary, FR in mNST increased (p<0.01) and that in DMNV decreased in response to CEL stimulation (p<0.05). In conclusions, our findings indicated that different loci of CNA may mediate differential effects on gastric activity via changes in the firing of brainstem neurons controlling gut activity.

Localization of sites within dorsal motor nucleus of vagus that affect gastric motility

1985 ◽  
Vol 249 (1) ◽  
pp. G73-G84 ◽  
Author(s):  
F. D. Pagani ◽  
W. P. Norman ◽  
D. K. Kasbekar ◽  
R. A. Gillis
Keyword(s):  
Heart Rate ◽  
Electrical Stimulation ◽  
Arterial Pressure ◽  
Gastric Motility ◽  
Motor Nucleus ◽  
Fast Blue ◽  
Medial Nucleus ◽  
Dorsal Motor Nucleus ◽  
Propantheline Bromide ◽  
Stimulation Of

The purpose of our study was to determine the localization of sites within the dorsal motor nucleus of the vagus (DMV) of the cat that when stimulated would increase gastric motility. To do this, two types of experiments were performed. First, the retrograde tracer fast blue was injected into the antrum and pylorus, and labeled neurons in the DMV were identified. Second, electrical stimulation was performed in areas of the DMV labeled with fast blue as well as in nearby areas with no labeling while monitoring gastric motility, arterial pressure, and heart rate. Results from the first type of studies revealed that peak labeling in the DMV occurred between 0.56 and 1.56 mm rostral to obex. Electrical stimulation in this area using 100 microA, 0.2 ms duration pulses, and 50 Hz resulted in increases in antral and pyloric contractions in 20 animals. The magnitude of pyloric and antral responses elicited by stimulation of the DMV generally correlated to the number of cell bodies labeled with fast blue within the DMV. No changes in arterial pressure occurred, and only a slight (-4%) decrease in heart rate was observed. Maximal increases in motility occurred with 20 Hz (antrum) or 100 Hz (pylorus). These increases in motility were maintained even at 200- and 400-Hz stimulation. Ipsilateral vagotomy or pretreatment with propantheline bromide prevented the increases in gastric motility produced by electrical stimulation of the DMV. Electrical stimulation of more rostral sites in the DMV, the medial nucleus of the solitary tract (NTS), and an area within 1.0 mm medial to the DMV resulted in attenuated or no motility responses. Stimulation of the medial nucleus of the NTS did result in pronounced slowing in heart rate (-61 +/- 21 beats/min). These results suggest that there is a localization of a “stomach area” within the DMV and that electrical stimulation of this area results in gastric motility responses that are mediated by vagal fibers projecting directly to the stomach. In addition, electrical stimulation of the DMV results in selective effects on the gastrointestinal tract in that no pronounced changes in heart rate and arterial pressure occur.

A reevaluation of the effects of stimulation of the dorsal motor nucleus of the vagus on gastric motility in the rat

2007 ◽  
Vol 292 (1) ◽  
pp. R291-R307 ◽  
Author(s):  
Maureen T. Cruz ◽  
Erin C. Murphy ◽  
Niaz Sahibzada ◽  
Joseph G. Verbalis ◽  
Richard A. Gillis
Keyword(s):  
Gastric Motility ◽  
Intragastric Balloon ◽  
Motor Nucleus ◽  
Inhibitory Effects ◽  
Inhibitory Pathways ◽  
Dorsal Motor Nucleus ◽  
Bilateral Vagotomy ◽  
Oxide Synthase ◽  
Intravenous Atropine ◽  
Stimulation Of

Our primary purpose was to characterize vagal pathways controlling gastric motility by microinjecting l-glutamate into the dorsal motor nucleus of the vagus (DMV) in the rat. An intragastric balloon was used to monitor motility. In 39 out of 43 experiments, microinjection of l-glutamate into different areas of the DMV rostral to calamus scriptorius (CS) resulted in vagally mediated excitatory effects on motility. We observed little evidence for inhibitory effects, even with intravenous atropine or with activation of gastric muscle muscarinic receptors by intravenous bethanechol. Inhibition of nitric oxide synthase with Nω-nitro-l-arginine methyl ester (l-NAME) HCl did not augment DMV-evoked excitatory effects on gastric motility. Microinjection of l-glutamate into the DMV caudal to CS produced vagally mediated gastric inhibition that was resistant to l-NAME. l-Glutamate microinjected into the medial subnucleus of the tractus solitarius (mNTS) also produced vagally mediated inhibition of gastric motility. Motility responses evoked from the DMV were always blocked by ipsilateral vagotomy, while responses evoked from the mNTS required bilateral vagotomy to be blocked. Microinjection of oxytocin into the DMV inhibited gastric motility, but the effect was never blocked by ipsilateral vagotomy, suggesting that the effect may have been due to diffusion of oxytocin to the mNTS. Microinjection of substance P and N-methyl-d-aspartate into the DMV also produced inhibitory effects attributable to excitation of nearby mNTS neurons. Our results do not support previous studies indicating parallel vagal excitatory and inhibitory pathways originating in the DMV rostral to CS. Our results do support previous findings of vagal inhibitory pathways originating in the DMV caudal to CS.

Aortic nerve-activated cardioinhibitory neurons and interneurons

1975 ◽  
Vol 229 (3) ◽  
pp. 783-789 ◽  
Author(s):  
J Schwaber ◽  
N Schneiderman
Keyword(s):  
Vagus Nerve ◽  
Nerve Stimulation ◽  
Baroreceptor Reflex ◽  
Motor Nucleus ◽  
Vagus Nerves ◽  
Antidromic Activation ◽  
Medial Nucleus ◽  
Aortic Nerve ◽  
Dorsal Motor Nucleus ◽  
Stimulation Of

Unit activity evoked by electrical stimulation of the aortic and vagus nerves was recorded in the dorsal motor nucleus and nucleus solitarius of unanesthetized rabbits. Cardioinhibitory cells which showed antidromic activation to stimulation of the vagus nerve and synaptic activation to stimulation of the aortic nerve were localized in lateral dorsal motor nucleus 0.5-0.8 mm anterior of the obex. Additionally, units were found that appeared to be interneurons in the medullary pathway subserving baroreceptor reflex effects on cardioinhibitory neurons. These cells were activated by aortic, and usually vagus, nerve stimulation, appeared to be polysynaptically activated, and were located in medial nucleus solitarius rostral to the obex. Neurons reflecting a cardiac rhythm but not activated by aortic nerve stimulation were also observed.

Neurons in the vagal complex of the rat respond to mechanical and chemical stimulation of the GI tract

1998 ◽  
Vol 274 (2) ◽  
pp. G331-G341 ◽  
Author(s):  
Xueguo Zhang ◽  
William E. Renehan ◽  
Ronald Fogel
Keyword(s):  
Acid Secretion ◽  
Gastric Motility ◽  
Extracellular Recording ◽  
Chemical Stimulation ◽  
Inhibitory Neurons ◽  
Motor Nucleus ◽  
Acid Solutions ◽  
Gi Tract ◽  
Dorsal Motor Nucleus ◽  
Stimulation Of

Perfusing the duodenum with acid solutions dramatically reduces gastric motility and acid secretion. We propose that the presence of acid in the proximal small intestine initiates a vagovagal reflex that excites inhibitory neurons in the nucleus of the solitary tract (NST) and reduces the activity of the neurons in the dorsal motor nucleus of the vagus nerve (DMNV). However, results from several investigations suggest that the relevant circuit may not be as simple as we had believed. The present study was designed to address this dilemma by employing intracellular and extracellular recording and intracellular labeling techniques to provide direct information on the activity of neurons in the NST and DMNV during and after intestinal exposure to acid solutions. The results obtained prove that NST and DMNV neurons respond to HCl in the duodenum. In some instances, these neurons were very stimulus specific, although the majority of the cells in our sample (47% of NST neurons and 86% of DMNV neurons) also responded to distension of the stomach and/or duodenum. It is important to note, however, that many of the more broadly responsive neurons in the dorsal vagal complex were able to distinguish between mechanical and chemical stimulation of the gastrointestinal (GI) tract. Most of the NST neurons that responded to duodenal perfusion with HCl were excited by this stimulus. Conversely, activity of most of the DMNV neurons decreased after the onset of the HCl stimulus. These findings verify the existence of a vagovagal reflex pathway initiated by duodenal perfusion with acid. Presumably, this reflex would decrease gastric motility and acid secretion, reducing the amount of acid that enters the duodenum and ultimately protecting the intestinal mucosa.

Release of vasopressin and oxytocin by paraventricular stimulation in rats

1990 ◽  
Vol 258 (1) ◽  
pp. R155-R159 ◽  
Author(s):  
R. Landgraf ◽  
T. Malkinson ◽  
T. Horn ◽  
W. L. Veale ◽  
K. Lederis ◽  
...  
Keyword(s):  
Electrical Stimulation ◽  
Paraventricular Nucleus ◽  
Arginine Vasopressin ◽  
Nucleus Tractus Solitarius ◽  
Motor Nucleus ◽  
Perfusion Technique ◽  
Dorsal Motor Nucleus ◽  
Osmotic Stimulus ◽  
Perfusion Period ◽  
Stimulation Of

The nucleus tractus solitarius/dorsal motor nucleus of the vagus nerve (NTS/DMV) area was perfused by the push-pull perfusion technique in anesthetized rats, and perfusates were assayed for arginine vasopressin (AVP) and oxytocin (OXT) immunoreactivity. As compared with controls, electrical stimulation of the ipsilateral paraventricular nucleus (PVN) resulted in increased amounts of both AVP (approximately 5-fold) and OXT (approximately 10-fold, P less than 0.05 each) in the perfusates. During the poststimulation perfusion period, peptide concentrations were found to return to control levels. Elevation of circulating AVP and OXT by an osmotic stimulus did not result in increases of AVP and OXT in NTS/DMV perfusates. These data suggest that AVP and OXT are released from NTS/DMV area fiber terminals during electrical stimulation of descending PVN neurons. Furthermore, they are consistent with the view that both peptides are involved as neurotransmitters in autonomic regulation.

Stimulation of the paraventricular nucleus modulates the activity of gut-sensitive neurons in the vagal complex

1999 ◽  
Vol 277 (1) ◽  
pp. G79-G90 ◽  
Author(s):  
Xueguo Zhang ◽  
Ronald Fogel ◽  
William E. Renehan
Keyword(s):  
Electrical Stimulation ◽  
Paraventricular Nucleus ◽  
Good Evidence ◽  
Small Subset ◽  
Motor Nucleus ◽  
Dorsal Motor Nucleus ◽  
Cephalic Phase ◽  
Stimulation Of ◽  
Vagal Function

There is good evidence that stimulation of the lateral hypothalamus excites neurons in the dorsal vagal complex (DVC), but the data regarding the role of the paraventricular nucleus (PVN) in vagal function are less clear. The purpose of this study was to clarify the effect of PVN stimulation on the activity of neurons in the DVC. We utilized extracellular and intracellular neuronal recordings with intracellular injections of a neuronal tracer to label individual, physiologically characterized neurons in the DVC of rats anesthetized with pentobarbital sodium. Most (80%) of the gut-sensitive dorsal motor nucleus of the vagus (DMNV) neurons characterized in this study exhibited a change in activity during electrical stimulation of the PVN. Stimulation of the PVN caused an increase in the spontaneous activity of 59% of the PVN-sensitive DMNV neurons, and the PVN was capable of modulating the response of a small subset of DMNV neurons to gastrointestinal stimuli. This study also demonstrated that the PVN was capable of influencing the activity of neurons in the nucleus of the solitary tract (NST). Electrical stimulation of the PVN decreased the basal activity of 66% of the NST cells that we characterized and altered the gastrointestinal response of a very small subset of NST neurons. It is likely that these interactions play a role in the modulation of a number of gut-related homeostatic processes. Increased or decreased activity in the descending pathway from the PVN to the DVC has the potential to alter ascending satiety signals, modulate vago-vagal reflexes and the cephalic phase of feeding, and affect the absorption of nutrients from the gastrointestinal tract.

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