Lipopolysaccharide effects on neuronal activity in rat basal forebrain and hypothalamus during sleep and waking

2000 ◽  
Vol 278 (3) ◽  
pp. R620-R627
Author(s):  
Xinzheng Xi ◽  
Linda A. Toth
Keyword(s):  
Neuronal Activity ◽  
Basal Forebrain ◽  
Preoptic Area ◽  
Intraperitoneal Administration ◽  
Brain Regions ◽  
Neuronal Firing ◽  
Firing Patterns ◽  
Firing Rates ◽  
Neuronal Mechanisms ◽  
The Brain

Peripheral administration of lipopolysaccharide (LPS) is associated with alterations in sleep and the electroencephalogram. To evaluate potential neuronal mechanisms for the somnogenic effects of LPS administration, we used unanesthetized rats to survey the firing patterns of neurons in various regions of rat basal forebrain (BF) and hypothalamus during spontaneous sleep and waking and during the epochs of sleep and waking that occurred after the intraperitoneal administration of LPS. In the brain regions studied, LPS administration was associated with altered firing rates in 39% of the neurons examined. A larger proportion of LPS-responsive units showed vigilance-related alterations in firing rates compared with nonresponsive units. Approximately equal proportions of LPS-responsive neurons showed increased and decreased firing rates after LPS administration, with some units in the lateral preoptic area of the hypothalamus showing particularly robust increases. These findings are consistent with other studies showing vigilance-related changes in neuronal activity in various regions of BF and hypothalamus and further demonstrate that peripheral LPS administration alters neuronal firing rates in these structures during both sleep and waking.

Do the suprachiasmatic nuclei oscillate in old rats as they do in young ones?

1993 ◽  
Vol 265 (5) ◽  
pp. R1216-R1222 ◽  
Author(s):  
E. Satinoff ◽  
H. Li ◽  
T. K. Tcheng ◽  
C. Liu ◽  
A. J. McArthur ◽  
...  
Keyword(s):  
Neuronal Activity ◽  
Brain Slices ◽  
Neuronal Firing ◽  
Suprachiasmatic Nuclei ◽  
Firing Rates ◽  
Behavioral Rhythms ◽  
Behavioral Rhythm ◽  
Old Rats ◽  
The Brain

The basis of the decline in circadian rhythms with aging was addressed by comparing the patterns of three behavioral rhythms in young and old rats with the in vitro rhythm of neuronal activity in the suprachiasmatic nuclei (SCN), the primary circadian pacemaker. In some old rats, rhythms of body temperature, drinking, and activity retained significant 24-h periodicities in entraining light-dark cycles; in others, one or two of the rhythms became aperiodic. When these rats were 23-27.5 mo old they were killed, and single-unit firing rates in SCN brain slices were recorded continuously for 30 h. There was significant damping of mean peak neuronal firing rates in old rats compared with young. SCN neuronal activities were analyzed with reference to previous entrained behavioral rhythm patterns of individual rats as well. Neuronal activity from rats with prior aperiodic behavioral rhythms was erratic, as expected. Neuronal activity from rats that were still maintaining significant 24-h behavioral rhythmicity at the time they were killed was erratic in most cases but normally rhythmic in others. Thus there was no more congruence between the behavioral rhythms and the brain slice rhythms than there was among the behavioral rhythms alone. These results, the first to demonstrate aberrant SCN firing patterns and a decrease in amplitude in old rats, imply that aging could either disrupt coupling between SCN pacemaker cells or their output, or cause deterioration of the pacemaking properties of SCN cells.

scholarly journals Confidence-Related Decision Making

2010 ◽  
Vol 104 (1) ◽  
pp. 539-547 ◽  
Author(s):  
Andrea Insabato ◽  
Mario Pannunzi ◽  
Edmund T. Rolls ◽  
Gustavo Deco
Keyword(s):  
Decision Making ◽  
Cognitive Functioning ◽  
Neuronal Activity ◽  
Emergent Property ◽  
Neuronal Responses ◽  
Attractor Network ◽  
Firing Rates ◽  
Integrate And Fire ◽  
The Brain ◽  
High Firing

Neurons have been recorded that reflect in their firing rates the confidence in a decision. Here we show how this could arise as an emergent property in an integrate-and-fire attractor network model of decision making. The attractor network has populations of neurons that respond to each of the possible choices, each biased by the evidence for that choice, and there is competition between the attractor states until one population wins the competition and finishes with high firing that represents the decision. Noise resulting from the random spiking times of individual neurons makes the decision making probabilistic. We also show that a second attractor network can make decisions based on the confidence in the first decision. This system is supported by and accounts for neuronal responses recorded during decision making and makes predictions about the neuronal activity that will be found when a decision is made about whether to stay with a first decision or to abort the trial and start again. The research shows how monitoring can be performed in the brain and this has many implications for understanding cognitive functioning.

scholarly journals Neuroanatomical Distribution of the Serotonergic System in the Brain and Retina of Holostean Fishes, The Sister Group to Teleosts

2020 ◽  
Vol 95 (1) ◽  
pp. 25-44
Author(s):  
Daniel Lozano ◽  
Agustín González ◽  
Jesús M. López
Keyword(s):  
Spinal Cord ◽  
Preoptic Area ◽  
Area Postrema ◽  
Sister Group ◽  
Brain Regions ◽  
Serotonergic System ◽  
Paraventricular Organ ◽  
Cell Groups ◽  
Actinopterygian Fishes ◽  
The Brain

Among actinopterygian fishes, holosteans are the phylogenetically closest group to teleosts but they have been much less studied, particularly regarding the neurochemical features of their central nervous system. The serotonergic system is one of the most important and conserved systems of neurotransmission in all vertebrates. By means of immunohistochemistry against serotonin (5-hydroxytryptamine), we have conducted a comprehensive and complete description of this system in the brain and retina of representative species of the 3 genera of holostean fishes, belonging to the only 2 extant orders, Amiiformes and Lepisosteiformes. Serotonin-immunoreactive cell groups were detected in the preoptic area, the hypothalamic paraventricular organ, the epiphysis, the pretectal region, the long and continuous column of the raphe, the spinal cord, and the inner nuclear layer of the retina. Specifically, the serotonergic cell groups in the preoptic area, the epiphysis, the pretectum, and the retina had never been identified in previous studies in this group of fishes. Widespread serotonergic innervation was observed in all main brain regions, but more abundantly in the subpallium, the hypothalamus, the habenula, the optic tectum, the so-called cerebellar nucleus, and the area postrema. The comparative analysis of these results with those in other groups of vertebrates reveals some extremely conserved features, such as the presence of serotonergic cells in the retina, the pineal organ, and the raphe column, while other characteristics, like the serotonergic populations in the preoptic area, the paraventricular organ, the pretectum, and the spinal cord are generally present in all fish groups, but have been lost in most amniotes.

The spontaneous firing patterns of forebrain neurons. III. Prevention of induced asymmetries in caudate neuronal firing rates by unilateral thalamic lesions

1977 ◽  
Vol 131 (2) ◽  
pp. 215-225 ◽  
Author(s):  
M.S. Levine ◽  
C.D. Hull ◽  
N.A. Buchwald ◽  
E. Garcia-Rill ◽  
A. Heller ◽  
...  
Keyword(s):  
Neuronal Firing ◽  
Spontaneous Firing ◽  
Firing Patterns ◽  
Firing Rates ◽  
Thalamic Lesions ◽  
Forebrain Neurons

Internal Pallidal Neuronal Activity During Mild Drug-Related Dyskinesias in Parkinson's Disease: Decreased Firing Rates and Altered Firing Patterns

2007 ◽  
Vol 97 (4) ◽  
pp. 2627-2641 ◽  
Author(s):  
J. I. Lee ◽  
L. Verhagen Metman ◽  
S. Ohara ◽  
P. M. Dougherty ◽  
J. H. Kim ◽  
...  
Keyword(s):  
Parkinson’S Disease ◽  
Parkinson's Disease ◽  
Firing Rate ◽  
Spike Trains ◽  
Neuronal Firing ◽  
Low Doses ◽  
Significant Group ◽  
Firing Patterns ◽  
Firing Rates ◽  
Before And After

The neuronal basis of hyperkinetic movement disorders has long been unclear. We now test the hypothesis that changes in the firing pattern of neurons in the globus pallidus internus (GPi) are related to dyskinesias induced by low doses of apomorphine in patients with advanced Parkinson's disease (PD). During pallidotomy for advanced PD, the activity of single neurons was studied both before and after administration of apomorphine at doses just adequate to induce dyskinesias (21 neurons, 17 patients). After the apomorphine injection, these spike trains demonstrated an initial fall in firing from baseline. In nine neurons, the onset of on was simultaneous with that of dyskinesias. In these spike trains, the initial fall in firing rate preceded and was larger than the fall at the onset of on with dyskinesias. Among the three neurons in which the onset of on occurred before that of dyskinesias, the firing rate did not change at the time of onset of dyskinesias. After injection of apomorphine, dyskinesias during on with dyskinesias often fluctuated between transient periods with dyskinesias and those without. Average firing rates were not different between these two types of transient periods. Transient periods with dyskinesias were characterized by interspike interval (ISI) independence, stationary spike trains, and higher variability of ISIs. A small but significant group of neurons demonstrated recurring ISI patterns during transient periods of on with dyskinesias. These results suggest that mild dyskinesias resulting from low doses of apomorphine are related to both low GPi neuronal firing rates and altered firing patterns.

Levels of specifically bound [3H]ketanserin compared with levels of serotonin (5HT) in the brain regions of juvenile and sexually recrudescing female rainbow trout, Oncorhynchus mykiss

2000 ◽  
Vol 78 (3) ◽  
pp. 228-236 ◽  
Author(s):  
Smriti M Agrawal ◽  
Robert J Omeljaniuk
Keyword(s):  
High Performance Liquid Chromatography ◽  
Liquid Chromatography ◽  
Electrochemical Detection ◽  
Binding Sites ◽  
High Performance ◽  
Preoptic Area ◽  
Brain Regions ◽  
Olfactory Lobe ◽  
Rainbow Trout Oncorhynchus Mykiss ◽  
The Brain

This study compared the distribution of specifically bound [3H]ketanserin (Bsp) with serotonin (5HT) in brain regions of juvenile and sexually recrudescing female trout. Amounts of Bsp varied widely among brain regions and consistently differed between juvenile and sexually recrudescing females. Levels of Bsp were significantly greater in the hypothalamus than the olfactory lobe, which were at least threefold greater than in all other tissues examined (Kruskal-Wallis test, p < 0.05). Bsp densities in the hypothalamus, preoptic area, and optic lobe were significantly greater in juveniles compared with corresponding tissues from sexually recrudescing females (Mann-Whitney U test, p < 0.05); in contrast, Bsp in olfactory lobe and spinal cord did not differ significantly between the two classes of fish. 5HT concentration was determined by high performance liquid chromatography - electrochemical detection (HPLC-EC) analysis. Biogenic amine standards eluted in a stereotypic pattern, with peaks consistently separable in time. 5HT concentration was significantly greater in hypothalamus than in olfactory lobe and undetectable in the pituitary (Kruskal-Wallis test, p < 0.05). Trends in distribution of Bsp and 5HT were comparable in the hypothalamus and preoptic area in juvenile and sexually recrudescing females. In general, density of specific [3H]ketanserin binding sites was directly related to 5HT content of brain regions in juvenile and sexually recrudescing females. 5HT concentrations (pmol/g tissue) were approximately 900-fold greater than Bsp (fmol/g tissue) in all brain regions, and approximately 300-fold greater than Bsp in the olfactory lobe. These results suggest important regulatory role(s) for 5HT in the trout preoptic-hypothalamo-hypophysial axis, which may differ from 5HT role(s) in trout olfactory lobe.Key words: high performance liquid chromatography - electrochemical detection, [3H]ketanserin, sexually recrudescing female trout.

Capsaicin Infused Into the PAG Affects Rat Tail Flick Responses to Noxious Heat and Alters Neuronal Firing in the RVM

2003 ◽  
Vol 90 (4) ◽  
pp. 2702-2710 ◽  
Author(s):  
Steve McGaraughty ◽  
Katharine L. Chu ◽  
Robert S. Bitner ◽  
Brenda Martino ◽  
Rachid El Kouhen ◽  
...  
Keyword(s):  
Spontaneous Activity ◽  
Neuronal Activity ◽  
Cell Activity ◽  
Brain Regions ◽  
Neuronal Firing ◽  
Tail Flick ◽  
Noxious Stimulation ◽  
Noxious Heat ◽  
Tail Flick Latency ◽  
Ventromedial Medulla

It is well established that the vanilloid receptor, VR1, is an important peripheral mediator of nociception. VR1 receptors are also located in several brain regions, yet it is uncertain whether these supraspinal VR1 receptors have any influence on the nociceptive system. To investigate a possible nociceptive role for supraspinal VR1 receptors, capsaicin (10 nmol in 0.4 μl) was microinjected into either the dorsal (dPAG) or ventral (vPAG) regions of the periaqueductal gray. Capsaicin-related effects on tail flick latency (immersion in 52°C water) and on neuronal activity (on-, off-, and neutral cells) in the rostral ventromedial medulla (RVM) were measured in lightly anesthetized rats. Administration of capsaicin into the dPAG but not the vPAG caused an initial hyperalgesic response followed later by analgesia (125 ± 20.96 min postinjection). The tail flick–related burst in on-cell activity was triggered earlier in the hyperalgesic phase and was delayed or absent during the analgesic phase. Spontaneous activity of on-cells increased at the onset of the hyperalgesic phase and decreased before and during the analgesic phase. The tail flick–related pause in off-cell activity as well as spontaneous firing for these cells was unchanged in the hyperalgesic phase. During the analgesic phase, off-cells no longer paused during noxious stimulation and had increased levels of spontaneous activity. Neutral cell firing was unaffected in either phase. Pretreatment with the VR1 receptor antagonist, capsazepine (10 nmol in 0.4 μl), into the dPAG blocked the capsaicin-induced hyperalgesia as well as the corresponding changes in on- and off-cell activity. VR1 receptor immunostaining was observed in the dPAG of untreated rats. Microinjection of capsaicin likely sensitized and then desensitized dPAG neurons affecting nocifensive reflexes and RVM neuronal activity. These results suggest that supraspinal VR1 receptors in the dPAG contribute to descending modulation of nociception.

scholarly journals Deep brain stimulation entrains local neuronal firing in human globus pallidus internus

2013 ◽  
Vol 109 (4) ◽  
pp. 978-987 ◽  
Author(s):  
Daniel R. Cleary ◽  
Ahmed M. Raslan ◽  
Jonathan E. Rubin ◽  
Diaa Bahgat ◽  
Ashwin Viswanathan ◽  
...  
Keyword(s):  
Parkinson’S Disease ◽  
Parkinson's Disease ◽  
Deep Brain Stimulation ◽  
Globus Pallidus ◽  
Neuronal Activity ◽  
Brain Stimulation ◽  
Spike Trains ◽  
Neuronal Firing ◽  
Firing Patterns ◽  
Deep Brain

Deep brain stimulation (DBS) in the internal segment of the globus pallidus (GPi) relieves the motor symptoms of Parkinson's disease, yet the mechanism of action remains uncertain. To address the question of how therapeutic stimulation changes neuronal firing in the human brain, we studied the effects of GPi stimulation on local neurons in unanesthetized patients. Eleven patients with idiopathic Parkinson's disease consented to participate in neuronal recordings during stimulator implantation surgery. A recording microelectrode and a DBS macroelectrode were advanced through the GPi in parallel until a single neuron was isolated. After a baseline period, stimulation was initiated with varying voltages and different stimulation sites. The intra-operative stimulation parameters (1–8 V, 88–180 Hz, 0.1-ms pulses) were comparable with the postoperative DBS settings. Stimulation in the GPi did not silence local neuronal activity uniformly, but instead loosely entrained firing and decreased net activity in a voltage-dependent fashion. Most neurons had decreased activity during stimulation, although some increased or did not change firing rate. Thirty-three of 45 neurons displayed complex patterns of entrainment during stimulation, and burst-firing was decreased consistently after stimulation. Recorded spike trains from patients were used as input into a model of a thalamocortical relay neuron. Only spike trains that occurred during therapeutically relevant voltages significantly reduced transmission error, an effect attributable to changes in firing patterns. These data indicate that DBS in the human GPi does not silence neuronal activity, but instead disrupts the pathological firing patterns through loose entrainment of neuronal activity.

Time-course of changes in firing rates and firing patterns of subthalamic nucleus neuronal activity after 6-OHDA-induced dopamine depletion in rats

2001 ◽  
Vol 899 (1-2) ◽  
pp. 142-147 ◽  
Author(s):  
Zhong-Ge Ni ◽  
Rabia Bouali-Benazzouz ◽  
Dong-Ming Gao ◽  
Alim-Louis Benabid ◽  
Abdelhamid Benazzouz
Keyword(s):  
Subthalamic Nucleus ◽  
Neuronal Activity ◽  
Time Course ◽  
Dopamine Depletion ◽  
Firing Patterns ◽  
Firing Rates

scholarly journals Spatio-temporal parameters for optical probing of neuronal activity

2021 ◽  
Author(s):  
Vincent R. Daria ◽  
Michael Lawrence Castañares ◽  
Hans-A. Bachor
Keyword(s):  
Neuronal Activity ◽  
Brain Regions ◽  
Mammalian Brain ◽  
Neuronal Circuits ◽  
Temporal Parameters ◽  
Brain Functions ◽  
Temporal Properties ◽  
Optical Probing ◽  
Spatio Temporal ◽  
The Brain

AbstractThe challenge to understand the complex neuronal circuit functions in the mammalian brain has brought about a revolution in light-based neurotechnologies and optogenetic tools. However, while recent seminal works have shown excellent insights on the processing of basic functions such as sensory perception, memory, and navigation, understanding more complex brain functions is still unattainable with current technologies. We are just scratching the surface, both literally and figuratively. Yet, the path towards fully understanding the brain is not totally uncertain. Recent rapid technological advancements have allowed us to analyze the processing of signals within dendritic arborizations of single neurons and within neuronal circuits. Understanding the circuit dynamics in the brain requires a good appreciation of the spatial and temporal properties of neuronal activity. Here, we assess the spatio-temporal parameters of neuronal responses and match them with suitable light-based neurotechnologies as well as photochemical and optogenetic tools. We focus on the spatial range that includes dendrites and certain brain regions (e.g., cortex and hippocampus) that constitute neuronal circuits. We also review some temporal characteristics of some proteins and ion channels responsible for certain neuronal functions. With the aid of the photochemical and optogenetic markers, we can use light to visualize the circuit dynamics of a functioning brain. The challenge to understand how the brain works continue to excite scientists as research questions begin to link macroscopic and microscopic units of brain circuits.

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