Characterization of the Sympatho-Facilitative Area Postrema Pathway

1980 ◽  
Vol 59 (s6) ◽  
pp. 255s-257s ◽  
Author(s):  
Karen L. Barnes ◽  
C. M. Ferrario
Keyword(s):  
Electrical Stimulation ◽  
Carotid Sinus ◽  
Area Postrema ◽  
Pressor Response ◽  
Baroreceptor Reflex ◽  
Solitary Tract ◽  
Anatomical Studies ◽  
Solitary Complex ◽  
Stimulation Of

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.

Interaction between carotid sinus baroreceptor and aortic nerve pressor reflexes in the dog

1979 ◽  
Vol 237 (6) ◽  
pp. H662-H667
Author(s):  
J. E. Kendrick ◽  
G. L. Matson
Keyword(s):  
Electrical Stimulation ◽  
Carotid Sinus ◽  
Pressor Response ◽  
Low Frequency ◽  
Carotid Sinus Nerve ◽  
Constant Frequency ◽  
Aortic Nerve ◽  
Frequency Stimulation ◽  
Pressor Reflexes ◽  
Stimulation Of

In dogs anesthetized with morphine-chloralose, strong, low-frequency (2 Hz) electrical stimulation of the aortic nerve (AN) causes pressure in the perfused hindlimbs to rise. This pressor response is followed by a large depressor phase upon cessation of stimulation. Simultaneous stimulation of the ipsilateral carotid sinus nerve (CSN) with intermittent trains of stimuli enhanced the AN pressor response by 113%. Similar stimulation of the contralateral CSN had little effect on the AN pressor response. Constant-frequency stimulation of the ipsilateral CSN also failed to enhance this response. Possible mechanisms of the interaction between these antagonistic reflexes were investigated. The results suggest that the augmentation of the AN pressor response results from a central neuronal interaction between these antagonistic reflexes.

scholarly journals Stimulation of the paraventricular nucleus modulates firing of neurons in the nucleus of the solitary tract

1999 ◽  
Vol 277 (2) ◽  
pp. R403-R411 ◽  
Author(s):  
Yu-Fei Duan ◽  
Irwin J. Kopin ◽  
David S. Goldstein
Keyword(s):  
Electrical Stimulation ◽  
Paraventricular Nucleus ◽  
Pressor Response ◽  
Hypothalamic Paraventricular Nucleus ◽  
Solitary Tract ◽  
Defense Reaction ◽  
Neuronal Inhibition ◽  
Pressor Responses ◽  
Baroreceptor Stimulation ◽  
Stimulation Of

The present study assessed whether the baroreflex inhibition elicited by electrical stimulation of the hypothalamic paraventricular nucleus (PVN) involves altered activity in the nucleus of the solitary tract (NTS). Unit recordings were made from 107 neurons in the NTS in anesthetized rabbits. Intravenous phenylephrine was used to induce a pressor response and to activate baroreflexes. Of the neurons that responded to pressor responses, two-thirds were excited and one-third was inhibited. Stimulation of the PVN inhibited 70% of the phenylephrine-responsive NTS neurons, with or without concurrent baroreceptor stimulation. When PVN stimulation was delivered concurrently with phenylephrine injection, more NTS neuronal inhibition and less excitation occurred than with phenylephrine alone. Usually PVN stimulation inhibited NTS neurons that were excited by pressor responses; less commonly, PVN stimulation excited NTS neurons that were inhibited by pressor responses. The findings are consistent with the view that PVN activation during the defense reaction inhibits baroreflexes by altering firing of NTS neurons.

Fos expression in ferret dorsal vagal complex after peripheral emetic stimuli

1994 ◽  
Vol 266 (4) ◽  
pp. R1118-R1126 ◽  
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.

Electrical stimulation of the carotid sinus lowers arterial pressure and improves heart rate variability in l-NAME hypertensive conscious rats

2020 ◽  
Vol 43 (10) ◽  
pp. 1057-1067 ◽  
Author(s):  
Gean Domingos-Souza ◽  
Fernanda Machado Santos-Almeida ◽  
César Arruda Meschiari ◽  
Nathanne S. Ferreira ◽  
Camila A. Pereira ◽  
...  
Keyword(s):  
Heart Rate ◽  
Heart Rate Variability ◽  
Electrical Stimulation ◽  
Arterial Pressure ◽  
Carotid Sinus ◽  
Conscious Rats ◽  
Stimulation Of

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

2017 ◽  
Vol 10 (1) ◽  
pp. 116-125 ◽  
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

Respiratory responses to aortic and carotid chemoreceptor activation in the dog

1991 ◽  
Vol 70 (6) ◽  
pp. 2539-2550 ◽  
Author(s):  
F. A. Hopp ◽  
J. L. Seagard ◽  
J. Bajic ◽  
E. J. Zuperku
Keyword(s):  
Electrical Stimulation ◽  
Carotid Body ◽  
Carotid Sinus ◽  
Chemical Stimulation ◽  
Respiratory Drive ◽  
Carotid Sinus Nerve ◽  
Nerve Activity ◽  
Respiratory Reflexes ◽  
Respiratory Responses ◽  
Stimulation Of

Respiratory responses arising from both chemical stimulation of vascularly isolated aortic body (AB) and carotid body (CB) chemoreceptors and electrical stimulation of aortic nerve (AN) and carotid sinus nerve (CSN) afferents were compared in the anesthetized dog. Respiratory reflexes were measured as changes in inspiratory duration (TI), expiratory duration (TE), and peak averaged phrenic nerve activity (PPNG). Tonic AN and AB stimulations shortened TI and TE with no change in PPNG, while tonic CSN and CB stimulations shortened TE, increased PPNG, and transiently lengthened TI. Phasic AB and AN stimulations throughout inspiration shortened TI with no changes in PPNG or the following TE; however, similar phasic stimulations of the CB and CSN increased both TI and PPNG and decreased the following TE. Phasic AN stimulation during expiration decreased TE and the following TI with no change in PPNG. Similar stimulations of the CB and CSN decreased TE; however, the following TI and PPNG were increased. These findings differ from those found in the cat and suggest that aortic chemoreceptors affect mainly phase timing, while carotid chemoreceptors affect both timing and respiratory drive.

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