Peripheral neural input to neurons of the middle cervical ganglion in the cat

In vitro studies were conducted on the middle cervical ganglion (MCG) of the cat by recording intracellular action potentials from its neurons. The purpose of this study was to examine the possibility of a peripheral synaptic input to the MCG. Preganglionic electrical stimulation, via the ventral ansa (VA) and dorsal ansa (DA) subclavia, and post-ganglionic electrical stimulation, via the ventrolateral cardiac nerve (VCN), evoked graded synaptic responses that led to the discharge of one or more action potentials in the 14 ganglia studied. The conduction velocity of these pathways ranged from 0.4 to 0.9 m/s. Ten percent of the cells impaled were inexcitable, even with direct intracellular depolarizing current, whereas 80% of the neurons studied received a synaptic input from fibers of both central and peripheral origin. In addition, subthreshold synaptic inputs from peripheral and central origin sum to discharge the cell, suggesting an integration of neural inputs in the MCG. These responses were blocked by d-tubocurarine chloride. This evidence indicates that sympathetic efferent nerve activity can be modified by peripheral excitatory inputs and that these inputs may function as pathways for a peripheral reflex at the level of the MCG.

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Peripheral neural input to neurons of the stellate ganglion in dog

AJP Regulatory Integrative and Comparative Physiology ◽

10.1152/ajpregu.1982.242.3.r237 ◽

1982 ◽

Vol 242 (3) ◽

pp. R237-R243

Author(s):

Z. J. Bosnjak ◽

J. L. Seagard ◽

J. P. Kampine

Keyword(s):

Electrical Stimulation ◽

Action Potentials ◽

Stellate Ganglion ◽

Afferent Input ◽

In Vivo Studies ◽

Organ Bath ◽

Efferent Nerve ◽

Stimulation Of

In vitro and in vivo studies were conducted on the stellate ganglion (SG) of the dog by recording action potentials from its nerves and its neurons. For in vitro preparations, the SG and its nerve trunks were dissected from the animal and secured in an organ bath. Peripheral input to the SG was produced by electrical stimulation of the ventral ansa subclavia (VA), dorsal ansa subclavia (DA), and stellate cardiac nerve (SC) in 15 ganglion preparations studied in vitro. Electrical stimulation of the VA elicited action potentials recorded at the DA. This conducting pathway did not involve direct anatomic continuity, since the evoked potentials were blocked by injection of hexamethonium chloride into the SG. Most neurons in the SG received synaptic input from fibers of both central and peripheral origin. In 12 in vivo preparations, all nerves to the SG except the VA were cut. When peripheral sympathetic afferent input to the SG was increased, some of the postganglionic fibers of the dissected DA exhibited an increase in efferent nerve discharge. This response was also blocked by hexamethonium chloride. These results indicate that some of the functions of the SG might be independent of the central nervous system.

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Electrical properties and synaptic connections to neurons in parasympathetic colonic ganglia of the cat

AJP Gastrointestinal and Liver Physiology ◽

10.1152/ajpgi.1984.247.1.g52 ◽

1984 ◽

Vol 247 (1) ◽

pp. G52-G61

Author(s):

J. Krier ◽

D. A. Hartman

Keyword(s):

Synaptic Input ◽

Action Potentials ◽

Distal Colon ◽

Nerve Fibers ◽

Synaptic Connections ◽

Electrophysiological Properties ◽

Intracellular Injection ◽

Spontaneous Action ◽

Spontaneous Action Potentials

Intracellular recording techniques were used in vitro to analyze the electrophysiological properties and synaptic connections to cat parasympathetic neurons in ganglia located on the serosal surface of the distal colon. Neurons were classified into two types. The first type exhibited spontaneous action potentials at regular and irregular interspike intervals. Spontaneous action potentials were 1) not abolished by superfusion of the ganglia with a modified Krebs solution containing low Ca2+, high Mg2+, or nicotinic ganglionic blocking agents, 2) reduced or abolished by intracellular injection of hyperpolarizing current, and 3) increased by intracellular injection of depolarizing current. We suggest that the generation of spontaneous action potentials may be due to an endogenous depolarizing mechanism and not to cholinergic synaptic input from other neurons located in the ganglia. The second type of neuron termed "quiescent" exhibited a stable transmembrane potential and elicited action potentials in response to electrical stimulation of nerve trunks. Both quiescent and spontaneously discharging neurons receive synaptic input from preganglionic fibers in the pelvic nerve and project their postganglionic axons to colonic nerve fibers that innervate effector structures in the colon.

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Activity-Dependent Axonal Plasticity: The Effects of Electrical Stimulation on Compound Action Potentials Recorded from the Mouse Nervous System In Vitro

The Open Neuroscience Journal ◽

10.2174/1874082000903010001 ◽

2009 ◽

Vol 3 (1) ◽

pp. 1-12 ◽

Cited By ~ 2

Author(s):

Zaghloul Ahmed ◽

Andrzej Wieraszko

Keyword(s):

Nervous System ◽

Electrical Stimulation ◽

Action Potentials ◽

Axonal Plasticity ◽

Compound Action Potentials ◽

Activity Dependent ◽

Compound Action

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Activity-Dependent Axonal Plasticity: The Effects of Electrical Stimulation on Compound Action Potentials Recorded from the Mouse Nervous System In Vitro

The Open Numerical Methods Journal ◽

10.2174/1876389800901010006 ◽

2009 ◽

Vol 1 (1) ◽

pp. 6-19

Author(s):

Thorsten Pampel

Keyword(s):

Nervous System ◽

Electrical Stimulation ◽

Action Potentials ◽

Axonal Plasticity ◽

Compound Action Potentials ◽

Activity Dependent ◽

Compound Action

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When the ostrich-algorithm fails: Blanking method affects spike train statistics

10.1101/166611 ◽

2017 ◽

Author(s):

Soheil Mottaghi ◽

Kevin Joseph ◽

Olaf Christ ◽

Thomas J. Feuerstein ◽

Ulrich G. Hofmann

Keyword(s):

Electrical Stimulation ◽

Spike Train ◽

Action Potentials ◽

Spike Rate ◽

Neuronal Tissue ◽

Electrophysiological Recordings ◽

Frequency Of Stimulation ◽

Theoretical Standpoint

1.AbstractElectrophysiological recordings of neuronal tissue face particular challenges when attempted during electrical stimulation, both in vivo and in vitro. Electrical stimulation may produce undesired electronic artifacts and thus render the recorded signal only partially useful. A commonly used remedy for these artifacts is to temporarily ground the input during the stimulation pulses. In the following study, we quantify the effects of this method on the spike train count, which is called "blanking". Starting a from theoretical standpoint, we deduce a loss of countable action potentials, depending on: width of the blanking window, Frequency of stimulation and neuronal activity. Calculations are corroborated by actual high SNR single cell recordings. We have to state, for therapeutically relevant frequencies of 130 Hz and realistic blanking windows of 2 ms, up to 27% of actual existing spikes are lost. We strongly advice careful and controlled use of blanking circuits when spike rate quantification is attempted.

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Effect of enkephalins on colonic mechanoreceptor synaptic input to inferior mesenteric ganglion

AJP Gastrointestinal and Liver Physiology ◽

10.1152/ajpgi.1987.252.1.g128 ◽

1987 ◽

Vol 252 (1) ◽

pp. G128-G135 ◽

Cited By ~ 1

Author(s):

H. D. Shu ◽

J. A. Love ◽

J. H. Szurszewski

Keyword(s):

Synaptic Input ◽

Action Potentials ◽

Input Resistance ◽

Inhibitory Neurons ◽

Intraluminal Pressure ◽

Resting Membrane Potential ◽

Inferior Mesenteric Ganglion ◽

Mesenteric Ganglion ◽

In Vitro Superfusion

The effects of leucine-enkephalin (Leu-Enk) on colonic mechanoreceptor input to the inferior mesenteric ganglion (IMG) and on colonic intraluminal pressure of the guinea pig were studied in vitro. Superfusion of the IMG with Leu-Enk decreased colonic, afferent mechanoreceptor synaptic input. In neurons in which mechanoreceptor input caused postsynaptic spikes, Leu-Enk decreased synaptic input and increased the basal intraluminal pressure of the colon. When mechanoreceptor input consisted of singly occurring excitatory postsynaptic potentials (EPSPs), Leu-Enk decreased the frequency of EPSPs but did not cause a change in colonic pressure. The inhibitory effects of Leu-Enk on synaptic transmission were antagonized by naloxone. In the isolated IMG, Leu-Enk converted synchronous action potentials in response to electrical stimulation of intermesenteric nerves to subthreshold EPSPs without a change in the resting membrane potential or input resistance. Action potentials elicited by depolarizing current pulses or by exogenous acetylcholine were unaltered by Leu-Enk. These data suggest that Leu-Enk increased colonic intraluminal pressure by acting on the presynaptic terminals of colonic mechanoreceptive neurons to reduce synaptic input to and output from the inhibitory neurons of the IMG.

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Electrophysiological and morphological characterization of neurons in stellate ganglion of cats

AJP Regulatory Integrative and Comparative Physiology ◽

10.1152/ajpregu.1985.248.3.r288 ◽

1985 ◽

Vol 248 (3) ◽

pp. R288-R292 ◽

Cited By ~ 1

Author(s):

Z. J. Bosnjak ◽

J. P. Kampine

Keyword(s):

Electrical Stimulation ◽

Synaptic Input ◽

Action Potentials ◽

Ganglion Cells ◽

Stellate Ganglion ◽

Morphological Characterization ◽

Dendritic Morphology ◽

Excitatory Responses ◽

Stimulation Of

We have studied the general morphology of cat stellate ganglion cells in relation to the synaptic input that each neuron receives. Horseradish peroxidase (HRP) was injected intracellularly into single neurons of the isolated cat stellate ganglia. Neurons of the stellate ganglion receive synaptic information from central and peripheral nerves. Electrical stimulation of the preganglionic nerves (T3 ramus), and postganglionic stimulation of the ventral or dorsal ansa subclavia, evoked graded excitatory responses that led to the discharge of one or more action potentials. The neurons receiving synaptic input from preganglionic and postganglionic nerves have a complex dendritic morphology. These neurons were located close to the postganglionic nerves and had an axon emerging from these nerves. Other neurons located closer to the preganglionic nerves had no identifiable axons leaving the ganglion and could not be excited antidromically by electrical stimulation. These neurons appear to be interneurons. These results indicate that neurons of the cat stellate ganglion are organized in a complex fashion that could be important in the integrative properties of these neurons.

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LY53857, a 5HT2 Receptor Antagonist, Delays Occlusion and Inhibits Platelet Aggregation in a Rabbit Model of Carotid Artery Occlusion

Thrombosis and Haemostasis ◽

10.1055/s-0038-1646420 ◽

1991 ◽

Vol 66 (03) ◽

pp. 355-360 ◽

Cited By ~ 4

Author(s):

Harve C Wilson ◽

William Coffman ◽

Anne L Killam ◽

Marlene L Cohen

Keyword(s):

Electrical Stimulation ◽

Platelet Aggregation ◽

Carotid Artery ◽

Receptor Antagonist ◽

Artery Occlusion ◽

Carotid Artery Occlusion ◽

Rabbit Platelet ◽

Rabbit Platelets ◽

5Ht2 Receptor

SummaryThe present study was designed to evaluate the effectiveness of the ergoline 5HT2 receptor antagonist, LY53857 in a rabbit model of vascular arterial occlusion. LY53857 (1 and 10 εM) inhibited serotonin amplified platelet aggregation responses to threshold concentrations of ADP in rabbit platelets in vitro. LY53857 (1 εM) not only inhibited the serotonin component of rabbit platelet aggregation, but also inhibited in vitro aggregation induced by ADP (48.7 ± 16.7% inhibition), collagen (76.1 ± 15.9% inhibition) and U46619 (65.2 ± 12.3% inhibition). The effectiveness of this ergoline 5HT2 receptor antagonist in blocking aggregation to ADP, collagen and U46619 may be related to its ability to inhibit a serotonin component of platelet aggregation since rabbit platelets possess high concentrations of serotonin that may be released during aggregation produced by other agents. Based on the effectiveness of LY53857 to inhibit rabbit platelet aggregation, we explored the ability of LY53857 to extend the time to carotid artery occlusion in rabbits following electrical stimulation of the artery. Reproducible carotid artery occlusion was induced in rabbits by moderate stenosis coupled to arterial cross clamping, followed by electrical stimulation. With this procedure, occlusion occurred at 47.0 ± 7 min (n = 30) after initiation of the electrical stimulation. Animals pretreated with LY53857 (50 to 500 εg/kg i.v.) showed a delay in the time to carotid artery occlusion (at 100 εg/kg i.v. occlusion time extended to 164 ± 16 min). Furthermore, ex vivo platelet aggregation from animals treated with LY53857 (300 εg/kg i.v.) resulted in 40.5% inhibition of platelet aggregation in response to the combination of ADP (1 εM) and serotonin (1 εM). These studies document the ability to obtain reproducible arterial occlusion in the rabbit and showed that intravenously administered LY53857 prolonged the time to carotid artery occlusion. Prolongation of carotid artery occlusion time was accompanied by inhibition of serotonin-amplified ADP-induced aggregation in rabbit platelets, an effect observed both in vitro and ex vivo. Thus, the rabbit is a useful model for studying the effectiveness of 5HT2 receptor antagonists in prolonging vascular occlusion induced by insult of the carotid artery.

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