Medullary cells of origin of vagal cardioinhibitory fibers in the pigeon. II. Electrical stimulation of the dorsal motor nucleus

1970 ◽  
Vol 140 (3) ◽  
pp. 321-342 ◽  
Author(s):  
David H. Cohen ◽  
Adrian M. Schnall
Keyword(s):  
Electrical Stimulation ◽  
Motor Nucleus ◽  
Dorsal Motor Nucleus ◽  
Cells Of Origin ◽  
Stimulation Of ◽  
Medullary Cells

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.

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.

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.

scholarly journals Properties and Interconnections of Trigeminal Interneurons of the Lateral Pontine Reticular Formation in the Rat

2001 ◽  
Vol 86 (5) ◽  
pp. 2583-2596 ◽  
Author(s):  
M.-J. Bourque ◽  
A. Kolta
Keyword(s):  
Electrical Stimulation ◽  
Reticular Formation ◽  
Motor Pattern ◽  
High Frequency Stimulation ◽  
Motor Nucleus ◽  
Trigeminal Motor Nucleus ◽  
Postsynaptic Potentials ◽  
Frequency Stimulation ◽  
Stimulation Of

Numerous evidence suggests that interneurons located in the lateral tegmentum at the level of the trigeminal motor nucleus contribute importantly to the circuitry involved in mastication. However, the question of whether these neurons participate actively to genesis of the rhythmic motor pattern or simply relay it to trigeminal motoneurons remains open. To answer this question, intracellular recordings were performed in an in vitro slice preparation comprising interneurons of the peritrigeminal area (PeriV) surrounding the trigeminal motor nucleus (NVmt) and the parvocellular reticular formation ventral and caudal to it (PCRt). Intracellular and extracellular injections of anterograde tracers were also used to examine the local connections established by these neurons. In 97% of recordings, electrical stimulation of adjacent areas evoked a postsynaptic potential (PSP). These PSPs were primarily excitatory, but inhibitory and biphasic responses were also induced. Most occurred at latencies longer than those required for monosynaptic transmission and were considered to involve oligosynaptic pathways. Both the anatomical and physiological findings show that all divisions of PeriV and PCRt are extensively interconnected. Most responses followed high-frequency stimulation (50 Hz) and showed little variability in latency indicating that the network reliably distributes inputs across all areas. In all neurons but one, excitatory postsynaptic potentials (EPSPs) or inhibitory postsynaptic potentials (IPSPs) were also elicited by stimulation of NVmt, suggesting the existence of excitatory and inhibitory interneurons within the motor nucleus. In a number of cases, these PSPs were reproduced by local injection of glutamate in lieu of the electrical stimulation. All EPSPs induced by stimulation of PeriV, PCRt, or NVmt were sensitive to ionotropic glutamate receptor antagonists 6-cyano-7-dinitroquinoxaline and d,l-2-amino-5-phosphonovaleric acid, while IPSPs were blocked by bicuculline and strychnine, antagonists of GABAA and glycine receptors. Examination of PeriV and PCRt intrinsic properties indicate that they form a fairly uniform network. Three types of neurons were identified on the basis of their firing adaptation properties. These types were not associated with particular regions. Only 5% of all neurons showed bursting behavior. Our results do not support the hypothesis that neurons of PeriV and PCRt participate actively to rhythm generation, but suggest instead that they are driven by rhythmical synaptic inputs. The organization of the network allows for rapid distribution of this rhythmic input across premotoneuron groups.

Distribution of vagal cardioinhibitory neurons in the medulla of the cat

1980 ◽  
Vol 238 (1) ◽  
pp. R57-R64 ◽  
Author(s):  
J. Ciriello ◽  
F. R. Calaresu
Keyword(s):  
Nucleus Tractus Solitarius ◽  
Border Region ◽  
Nucleus Ambiguus ◽  
Motor Nucleus ◽  
Dorsal Motor Nucleus ◽  
Antidromic Stimulation ◽  
Low Threshold ◽  
Vagal Bradycardia ◽  
Medullary Nuclei ◽  
Stimulation Of

Experiments were done in cats anesthetized with chloralose, paralyzed and artificially ventilated cats to obtain electrophysiological evidence on the medullary site of origin of vagal cardioinhibitory fibers. The regions of the nucleus ambiguus (AMB), dorsal motor nucleus of the vagus (DMV), nucleus tractus solitarius (NTS), and external cuneate nucleus (ECN) were systematically explored for units responding both to antidromic stimulation of the cardiac branches of the vagus (CBV) and to orthodromic stimulation of the carotid sinus and aortic depressor nerves. Eighty-six single units conforming to these criteria were found in the medulla: 30 in the AMB, 26 in the DMV, 12 in the NTS, 8 in the NTS-DMV border region, and 10 in the ECN. Antidromically evoked spikes had durations of 0.5--2.5 ms and followed stimulation frequencies of 20--500 Hz. The axons of these units conducted at velocities of 3.3--20.8 m/s. The specificity of activation of medullary units by cardioinhibitory fibers was tested in 11 units, which were found to respond consistently with an antidromic spike to stimulation of CBV but not to stimulation of the thoracic vagus. In eight spinal animals low threshold (less than 15 microA) sites eliciting vagal bradycardia were found in the same medullary nuclei where cardioinhibitory units had been located. These results indicate that vagal cardioinhibitory axons, originate in at least three medullary nuclei, the AMB, DMV, and NTS. Unit activity from the ECN may have been recorded from carioinhibitory fibers because of the short duration of the spike potentials.

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