Influence of electrical stimulation of the region of the area postrema/nucleus of the solitary tract on unit activity in the anterior raphe and the cortical electroencephalogram of the rat

1. The mechanism by which the area postrema augments central sympathetic drive during electrical stimulation is presently unknown. This pathway may involve either direct facilitation of brain-stem vasomotor neurons or inhibition of the sympatho-inhibitory baroreceptor relay in the nucleus tractus solitarii. 2. The present study employed selective lesions within the solitary tract nucleus to assess the participation of the primary baroreceptor relay in the pressor response during electrical stimulation of the area postrema. 3. The magnitude of the pressor response was unchanged after destruction of the solitary tract and lateral solitary nucleus which centrally interrupted the baroreceptor reflex. However, microknife cuts through the medial solitary nucleus, which spared the carotid sinus reflex, significantly reduced the magnitude of the area postrema pressor response. 4. Previous anatomical studies support these results and confirm that, although the area postrema pressor pathway traverses the most medial portion of the solitary complex, it does not produce augmented sympathetic outflow by inhibition of the primary baroreflex relay.

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Fos expression in ferret dorsal vagal complex after peripheral emetic stimuli

AJP Regulatory Integrative and Comparative Physiology ◽

10.1152/ajpregu.1994.266.4.r1118 ◽

1994 ◽

Vol 266 (4) ◽

pp. R1118-R1126 ◽

Cited By ~ 3

Author(s):

F. M. Boissonade ◽

K. A. Sharkey ◽

J. S. Davison

Keyword(s):

Electrical Stimulation ◽

Hypertonic Saline ◽

Area Postrema ◽

Dorsal Vagal Complex ◽

Solitary Tract ◽

Communicating Branch ◽

Nuclear Phosphoprotein ◽

Fos Expression ◽

Hypertonic Saline Injection ◽

Stimulation Of

The aim of this study was to investigate neuronal activation in the dorsal vagal complex of the halothane-anesthetized ferret after peripheral emetic stimuli. Neuronal activity was studied by examining the distribution of the nuclear phosphoprotein Fos using immunohistochemistry. The emetic stimuli used were electrical stimulation of the supradiaphragmatic vagal communicating branch (SVCB) or intraduodenal injection of hypertonic saline. Electrical stimulation of the SVCB induced the densest Fos expression within the medial subnucleus of the nucleus of the solitary tract. After hypertonic saline injection, the greatest density of Fos-positive nuclei was observed within the area postrema and also in the medial subnucleus of the nucleus of the solitary tract. It was concluded that the emetic response to hypertonic saline involves neurons in both the area postrema and the nucleus of the solitary tract, especially the medial subnucleus, and that the medial subnucleus is important in the emetic response to SVCB stimulation.

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Effects of electrical stimulation of the lateral habenula on single-unit activity of raphe neurons

Experimental Neurology ◽

10.1016/0014-4886(79)90102-x ◽

1979 ◽

Vol 65 (2) ◽

pp. 326-342 ◽

Cited By ~ 57

Author(s):

W.C. Stern ◽

A. Johnson ◽

J.D. Bronzino ◽

P.J. Morgane

Keyword(s):

Electrical Stimulation ◽

Unit Activity ◽

Single Unit ◽

Single Unit Activity ◽

Lateral Habenula ◽

Raphe Neurons ◽

Stimulation Of

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Effect of Electrical Stimulation of the Nucleus of the Solitary Tract on Electroencephalographic Spectral Power and the Sleep–Wake Cycle in Freely Moving Cats

Brain Stimulation ◽

10.1016/j.brs.2016.08.012 ◽

2017 ◽

Vol 10 (1) ◽

pp. 116-125 ◽

Cited By ~ 5

Author(s):

D. Martínez-Vargas ◽

A. Valdés-Cruz ◽

V.M. Magdaleno-Madrigal ◽

R. Fernández-Mas ◽

S. Almazán-Alvarado

Keyword(s):

Electrical Stimulation ◽

Spectral Power ◽

Solitary Tract ◽

Freely Moving ◽

Freely Moving Cats ◽

Stimulation Of

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Modification of cortical, reticular and hippocampal unit activity by nicotine in the rabbit

American Journal of Physiology-Legacy Content ◽

10.1152/ajplegacy.1960.198.3.515 ◽

1960 ◽

Vol 198 (3) ◽

pp. 515-518 ◽

Cited By ~ 26

Author(s):

C. W. Dunlop ◽

C. Stumpf ◽

D. S. Maxwell ◽

W. Schindler

Keyword(s):

Electrical Stimulation ◽

Unit Activity ◽

Eeg Changes ◽

Stimulation Of

Of the three regions examined, the hippocampus had the lowest threshold for nicotine effects. Following nicotine injection, regularization of the EEG in all regions was accompanied by increased unit excitability, and during seizures the unit activity was depressed. Modification of neocortical and reticular unit activity without any concomitant EEG changes in these regions was occasionally recorded after nicotine injection. Further experiments indicated that these changes of unit activity were due to alterations in hippocampal excitability elicited by the drug. Electrical stimulation of the hippocampus which evoked regularization and seizure discharges similarly modified the reticular unit excitability, but no conclusive results could be obtained regarding the hippocampal influence on neocortical units.

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Integration of cornea and cardiorespiratory afferents in the nucleus of the solitary tract of the rat

AJP Heart and Circulatory Physiology ◽

10.1152/ajpheart.00678.2001 ◽

2002 ◽

Vol 282 (4) ◽

pp. H1278-H1287 ◽

Cited By ~ 8

Author(s):

Pedro Boscan ◽

Julian F. R. Paton

Keyword(s):

Electrical Stimulation ◽

Solitary Tract ◽

Peripheral Chemoreceptor ◽

Single Unit Recordings ◽

Degree Of Convergence ◽

High Degree ◽

Working Heart ◽

Stimulation Of ◽

Nerve Discharge

We determined the activity of neurons within the nucleus of the solitary tract (NTS) after stimulation of the cornea and assessed whether this input affected the processing of baroreceptor and peripheral chemoreceptor inputs. In an in situ, unanesthetized decerebrate working heart-brain stem preparation of the rat, noxious mechanical or electrical stimulation was applied to the cornea, and extracellular single unit recordings were made from NTS neurons. Cornea nociceptor stimulation evoked bradycardia and an increase in the cycle length of the phrenic nerve discharge. Of 90 NTS neurons with ongoing activity, corneal stimulation excited 51 and depressed 39. There was a high degree of convergence to these NTS neurons from either baroreceptors or chemoreceptors. The excitatory synaptic response in 12 of 19 baroreceptive and 10 of 15 chemoreceptive neurons was attenuated significantly during concomitant electrical stimulation of the cornea. This inhibition was GABAA receptor mediated, being blocked by pressure ejection of bicuculline. Thus the NTS integrates information from corneal receptors, some of which converges onto neurons mediating reflexes from baroreceptors and chemoreceptors to inhibit these inputs.

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Inhibition of renal sympathetic nervous activity by area postrema stimulation in rabbits

AJP Heart and Circulatory Physiology ◽

10.1152/ajpheart.1987.253.1.h91 ◽

1987 ◽

Vol 253 (1) ◽

pp. H91-H99 ◽

Cited By ~ 2

Author(s):

E. M. Hasser ◽

D. O. Nelson ◽

J. R. Haywood ◽

V. S. Bishop

Keyword(s):

Heart Rate ◽

Electrical Stimulation ◽

Arterial Pressure ◽

Nucleus Tractus Solitarius ◽

Area Postrema ◽

Nervous Activity ◽

Sympathetic Nervous Activity ◽

Consistent Change ◽

Renal Sympathetic ◽

Stimulation Of

This study investigated the effect of chemical and electrical stimulation of the area postrema on renal sympathetic nerve activity (RSNA), arterial pressure, and heart rate in urethan-anesthetized rabbits. Electrical stimulation of the area postrema at 2, 5, 10, 20, 40, and 80 Hz using constant currents of 7.5, 15, and 30 microA (pulse duration = 0.3 ms, train duration = 5 s) produced progressive decreases in RSNA and heart rate, with no consistent change in arterial pressure. To control for electrical activation of fibers of passage in or near the area postrema, L-glutamate was injected into the area postrema using glass micropipettes. Micropressure injection of L-glutamate (10 mM) in volumes of 5-10 nl produced rapid decreases in RSNA averaging 27 +/- 5% (P less than 0.05) accompanied by a small bradycardia. The effects of electrical stimulation of the area postrema, but not the adjacent nucleus tractus solitarius, were totally eliminated by micropressure injection of kainic acid (40 ng in 40 nl) into the area postrema. During continuous electrical stimulation of the area postrema using parameters that produced small decrements in RSNA and heart rate, the slope of the line relating baroreflex inhibition of RSNA to increases in arterial pressure during graded infusions of phenylephrine was significantly enhanced (-6.77 +/- 1.30 vs. -3.81 +/- 0.66% RSNA/mmHg). These data are consistent with the hypothesis that activation of neurons in the area postrema results in an inhibition of RSNA. Furthermore, stimulation of the area postrema augments baroreflex inhibition of RSNA during increases in arterial pressure with phenylephrine.

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