Effects of endogenous pyrogen and prostaglandin E2 on hypothalamic neurons in rat brain slices

1987 ◽  
Vol 65 (6) ◽  
pp. 1382-1388 ◽  
Author(s):  
Tatsuo Watanabe ◽  
Akio Morimoto ◽  
Naotoshi Murakami
Keyword(s):  
Prostaglandin E2 ◽  
Rat Brain ◽  
Brain Tissue ◽  
Neuronal Activity ◽  
Brain Slice ◽  
Brain Slices ◽  
Prostaglandin E ◽  
Recording Electrode ◽  
Culture Chamber ◽  
Endogenous Pyrogen

We investigated the effects of endogenous pyrogen and prostaglandin E2 (PGE2) on the preoptic and anterior hypothalamic (POAH) neurons using brain slice preparations from the rat. Partially purified endogenous pyrogen did not change the activities of most of the neurons in the POAH region when applied locally through a micropipette attached to the recording electrode in proximity to the neurons. This indicates that partially purified endogenous pyrogen does not act directly on the neuronal activity in the POAH region. The partially purified endogenous pyrogen, applied into a culture chamber containing a brain slice, facilitated the activities in 24% of the total neurons tested, regardless of the thermal specificity of the neurons. Moreover, PGE2 added to the culture chamber facilitated 48% of the warm-responsive, 33% of the cold-responsive, and 29% of the thermally insensitive neurons. The direction of change in neuronal activity induced by partially purified endogenous pyrogen appears to be almost the same as that induced by PGE2 when these substances were applied by perfusion to the same neuron in the culture chamber. These results suggest that partially purified pyrogen applied to the perfusate of the culture chamber stimulates some constituents of brain tissue to synthesize and release prostaglandin, which in turn affects the neuronal activity of the POAH region.

Effects of endogenous pyrogen and prostaglandin E2 on hypothalamic neurons in guinea pig brain slices

1987 ◽  
Vol 63 (1) ◽  
pp. 175-180 ◽  
Author(s):  
T. Ono ◽  
A. Morimoto ◽  
T. Watanabe ◽  
N. Murakami
Keyword(s):  
Prostaglandin E2 ◽  
Neuronal Activity ◽  
Neuronal Response ◽  
Brain Slices ◽  
Direct Effects ◽  
Endogenous Pyrogen ◽  
Tissue Slices ◽  
Thermoresponsive Neurons ◽  
The Individual ◽  
Guinea Pig Brain

To investigate the direct effects of endogenous pyrogen (EP) and prostaglandin E2 (PGE2) on the activity of neurons in the preoptic and anterior hypothalamic (PO-AH) region, single-unit activity was recorded from brain tissue slices prepared from the PO-AH region of guinea pigs. When EP was applied into the perfusate 18% of warm-responsive neurons decreased their activity, and 23% of warm-responsive neurons increased their activity. Most of the thermally insensitive neurons did not respond to EP. PGE2 inhibited 29% of warm-responsive neurons and facilitated 15% of them. Moreover, when EP and PGE2 were applied to the same neurons at different times, the same directions of changes in neuronal activity were observed in 72% of total neurons examined. These results suggest that EP and PGE2 change the neuronal activity of the thermoresponsive neurons in the PO-AH region involved in fever induction. However, by these results, the direction of neuronal response induced by these substances could not be generally categorized based on the thermoresponsiveness of the individual neuron.

Intracellular pH in rat brain in vivo and in brain slices

1992 ◽  
Vol 70 (S1) ◽  
pp. S269-S277 ◽  
Author(s):  
Joseph C. LaManna ◽  
J. Keven Griffith ◽  
Boris R. Cordisco ◽  
Chii-Wann Lin ◽  
W. David Lust
Keyword(s):  
Cardiac Arrest ◽  
Rat Brain ◽  
Intracellular Ph ◽  
Brain Slice ◽  
Spatial Information ◽  
Brain Slices ◽  
Neutral Red ◽  
Hydrogen Ion ◽  
Sodium Hydrogen

Intracellular pH can be measured quantitatively in rat brain in vivo and in vitro using spectrophotometric detection of the vital dye neutral red. This method preserves spatial information and is compatible with microhistochemistry. The intracellular pH indicated by this method is in close agreement with that indicated by 31P-NMR spectroscopy. During ischemia, intracellular acidification is correlated with tissue lactate accumulation. The spatial distribution of pH values becomes more heterogeneous as the tissue becomes more acidic. Resuscitation from total cerebral ischemia produced by cardiac arrest results in rapid intracellular realkalinization. This realkalinization is at least partially inhibited by amiloride pretreatment. Some neuronal populations, especially in the hippocampal CA1 and CA4 regions, may become more acidic during ischemia and realkalinize more slowly after reperfusion than other tissue regions. The intracellular pH of hippocampal brain slice preparations is more alkaline than expected from in vivo studies. The intracellular pH of the brain slice can be acidified to near neutrality by specific inhibitors of the sodium/hydrogen ion exchanger.Key words: hippocampal brain slice, intracellular pH, neutral red, cardiac arrest and resuscitation, sodium/hydrogen ion exchanger.

Acute hypoxia induces elevation of ornithine decarboxylase activity in neonatal rat brain slices

1995 ◽  
Vol 7 (3) ◽  
pp. 385 ◽  
Author(s):  
LD Longo ◽  
S Packianathan
Keyword(s):  
Rat Brain ◽  
Ornithine Decarboxylase ◽  
Bovine Serum ◽  
Brain Slice ◽  
Brain Slices ◽  
Neonatal Rat ◽  
Newborn Rat ◽  
Rat Brain Slice

Recent studies in vivo have demonstrated that ornithine decarboxylase (ODC) activity in the fetal rat brain is elevated 4-5-fold by acute maternal hypoxia. This hypoxic-associated increase is seen in the rat brain in both the newborn and the adult. Because of the intimate involvement of ODC in transcription and translation, as well as in growth and development, it is imperative that the manner in which hypoxia affects the regulation of this enzyme be better understood. In order to achieve this, a brain preparation in vitro was required to eliminate the confounding effects of the dam on the fetal and newborn brain ODC activity in vivo. Therefore, brain slices from 3-4-day-old (P-3) newborn rats were utilized to test the hypothesis that ODC activity increases in response to hypoxia in vitro. Cerebral slices from the P-3 rat pups were allowed to equilibrate and recover in artificial cerebrospinal fluid (ACSF) continuously bubbled with a mixture of 95% O2 and 5% CO2 for 1 h before beginning hypoxic exposures. Higher basal ODC activities were obtained by treating the slices with 0.03% fetal bovine serum (FBS) and 0.003% bovine serum albumin (BSA), rather than with ACSF alone. Hypoxia was induced in the slices by replacing the gas with 40%, 21%, 10%, or 5% O2, all with 5% CO2 and balance N2. With FBS and BSA treatment, ODC activity was maintained at about 0.15-0.11 nM CO2 mg-1 protein h-1 throughout the experiment, which was 2-3-fold higher than that without FBS and BSA. ODC activity increased significantly and peaked between 1 h and 2 h after initiation of hypoxia. For instance, with 21% O2, ODC activity increased approximately 1.5-fold at 1 h and approximately 2-fold at 2 h. These studies demonstrate that: (1) the hypoxic-induced increases observed in vivo in the fetal and newborn rat brain ODC activity can be approximated in a newborn rat brain slice preparation in vitro; (2) newborn rat brain slice preparations may provide an alternative to methods in vivo or cell culture methods for studying the regulation of acute hypoxic-induced enzymes; and (3) high, stable baseline ODC activities in brain slices suggest that the cells in the slice are capable of active metabolism if FBS and BSA are available to mimic conditions in vivo.

scholarly journals Involvement of Hyperpolarization-Activated Cyclic Nucleotide-Gated Channel 3 in Oxytocin Neuronal Activity in Lactating Rats With Pup Deprivation

ASN NEURO ◽  
2020 ◽  
Vol 12 ◽  
pp. 175909142094465 ◽  
Author(s):  
Dongyang Li ◽  
Haitao Liu ◽  
Xiaoyu Liu ◽  
Hongyang Wang ◽  
Tong Li ◽  
...  
Keyword(s):  
Neuronal Activity ◽  
Cyclic Nucleotide ◽  
Brain Slices ◽  
Oxytocin Receptor ◽  
Molecular Association ◽  
Cyclooxygenase 2 ◽  
Enzyme Linked Immunosorbent Assay ◽  
Prostaglandin E ◽  
Western Blots ◽  
Gated Channel

Oxytocin, a hypothalamic neuropeptide essential for breastfeeding, is mainly produced in oxytocin neurons in the supraoptic nucleus (SON) and paraventricular nucleus. However, mechanisms underlying oxytocin secretion, specifically the involvement of hyperpolarization-activated cyclic nucleotide-gated channel 3 (HCN3) in oxytocin neuronal activity, remain unclear. Using a rat model of intermittent and continuous pup deprivation (PD) at the middle stage of lactation, we analyzed the contribution of HCN3 in oxytocin receptor (OTR)-associated signaling cascade to oxytocin neuronal activity in the SON. PD caused maternal depression, anxiety, milk shortage, involution of the mammary glands, and delays in uterine recovery, particularly in continuous PD. PD increased hypothalamic but not plasma oxytocin levels in enzyme-linked immunosorbent assay. In the SON, PD increased c-Fos expression but reduced expressions of cyclooxygenase-2 and HCN3 in Western blots and/or immunohistochemistry. Moreover, PD significantly increased the molecular association of OTR with HCN3 in coimmunoprecipitation. In brain slices, inhibition of HCN3 activity with DK-AH269 blocked prostaglandin E2-evoked increase in the firing activity and burst discharge in oxytocin neurons in patch-clamp recordings. In addition, oxytocin-evoked increase in the molecular association between OTR and HCN3 in brain slices of the SON was blocked by pretreatment with indomethacin, an inhibitor of cyclooxygenase-2. These results indicate that normal activity of oxytocin neurons is under the regulation of an oxytocin receptor–cyclooxygenase-2–HCN3 pathway and that PD disrupts maternal behavior through increasing intranuclear oxytocin secretion in the SON but likely reducing bolus oxytocin release into the blood through inhibition of HCN3 activity.

scholarly journals Image-based stroke rat brain atrophy volume and infarct volume computation

2020 ◽  
Vol 76 (12) ◽  
pp. 10090-10121
Author(s):  
Yung-Kuan Chan ◽  
Chun-Fu Hong ◽  
Meng-Hsiun Tsai ◽  
Ya-Lan Chang ◽  
Ping-Hsuan Sun
Keyword(s):  
Ischemic Stroke ◽  
Rat Brain ◽  
Brain Slice ◽  
Infarct Volume ◽  
Brain Slices ◽  
Artery Occlusion ◽  
Tetrazolium Chloride ◽  
Rat Brain Slice ◽  
Cerebral Artery Occlusion ◽  
The Brain

Abstract Stroke is one of the leading causes of death as well as results in a massive economic burden for society. Stroke is a cerebrovascular disease mainly divided into two types: ischemic stroke and hemorrhagic stroke, which, respectively, refer to the partial blockage and bleeding inside brain blood vessels. Both stroke types lead to nutrient and oxygen deprivation in the brain, which ultimately cause brain damage or death. This study focuses on ischemic stroke in rats with middle cerebral artery occlusion (MCAO) as experimental subjects, and the volumes of infarct and atrophy are calculated based on the brain slice images of rat brains stained with 2,3,5-triphenyl tetrazolium chloride. In this study, a stroke rat brain infarct and atrophy volumes computation system (SRBIAVC system) is developed to segment the infarcts and atrophies from the rat brain slice images. Based on the segmentation results, the infarct and atrophy volumes of a rat brain can be computed. In this study, 168 images of brain slices cut from 28 rat brains with MCAO are used as the test samples. The experimental results show that the segmentation results obtained by the SRBIAVC system are close to those obtained by experts.

Biochemistry

1936 ◽  
Vol 82 (339) ◽  
pp. 431-433
Author(s):  
J. H. Quastel
Keyword(s):  
Nervous System ◽  
Brain Tissue ◽  
Brain Slice ◽  
Brain Slices ◽  
Ringer Solution ◽  
Living Animal ◽  
Dominant Form ◽  
Straight Line ◽  
The Brain

I want to speak of the work we have been doing in Cardiff on the metabolism of the nervous system. The work was carried out there because of the importance of the narcosis treatment. It seemed to us there a pity that a treatment such as that should be given up because of the considerable toxicity possible in relation to it. The research was undertaken to see if we could diminish the toxicity, at the same time seeking an idea as to how narcotics work. I ask that you will realize that the main substance burned by the brain is glucose. The dominant form of metabolism in the nervous system is connected with the breakdown of glucose and lactic acid, and this can be proved by experiment in the living animal and with brain-tissue in vitro. In doing experiments we are not able to carry out work with human brain, because we cannot get human tissue fresh enough, so we have to carry out experiments with animals. They are carried out in this way. We cut slices of the cortex of the brain as soon as the animal is dead, that is to say, within ten minutes of death the brain is out and slices have been cut. They are placed in a physiological medium in the presence of glucose, and we follow the metabolism of that tissue, which allows us to estimate the amount of oxygen being taken up by the brain. If luminal, chloretone, hyoscine or somnifaine be placed with the brain-tissue, then the respiration, instead of being at the usual level, starts lower down, and maintains a straight line. We wanted to see whether this action is reversible or irreversible. If the latter, then on removing the brain-slices from the narcotic it should no longer behave like a normal piece of tissue. Actually, when the brain-slice is removed and placed in Ringer solution, with no narcotic, the respiration goes up and becomes equal to that shown by the slice which had no narcotic. That is to say, the process is reversible.

scholarly journals Spindle-Like Thalamocortical Synchronization in a Rat Brain Slice Preparation

2000 ◽  
Vol 84 (2) ◽  
pp. 1093-1097 ◽  
Author(s):  
Virginia Tancredi ◽  
Giuseppe Biagini ◽  
Margherita D'Antuono ◽  
Jacques Louvel ◽  
René Pumain ◽  
...  
Keyword(s):  
Rat Brain ◽  
Kynurenic Acid ◽  
Brain Slice ◽  
Excitatory Amino Acid ◽  
Brain Slices ◽  
Reticular Nucleus ◽  
Antidromic Responses ◽  
Rat Brain Slice

We obtained rat brain slices (550–650 μm) that contained part of the frontoparietal cortex along with a portion of the thalamic ventrobasal complex (VB) and of the reticular nucleus (RTN). Maintained reciprocal thalamocortical connectivity was demonstrated by VB stimulation, which elicited orthodromic and antidromic responses in the cortex, along with re-entry of thalamocortical firing originating in VB neurons excited by cortical output activity. In addition, orthodromic responses were recorded in VB and RTN following stimuli delivered in the cortex. Spontaneous and stimulus-induced coherent rhythmic oscillations (duration = 0.4–3.5 s; frequency = 9–16 Hz) occurred in cortex, VB, and RTN during application of medium containing low concentrations of the K+ channel blocker 4-aminopyridine (0.5–1 μM). This activity, which resembled electroencephalograph (EEG) spindles recorded in vivo, disappeared in both cortex and thalamus during application of the excitatory amino acid receptor antagonist kynurenic acid in VB ( n = 6). By contrast, cortical application of kynurenic acid ( n = 4) abolished spindle-like oscillations at this site, but not those recorded in VB, where their frequency was higher than under control conditions. Our findings demonstrate the preservation of reciprocally interconnected cortical and thalamic neuron networks that generate thalamocortical spindle-like oscillations in an in vitro rat brain slice. As shown in intact animals, these oscillations originate in the thalamus where they are presumably caused by interactions between RTN and VB neurons. We propose that this preparation may help to analyze thalamocortical synchronization and to understand the physiopathogenesis of absence attacks.

scholarly journals Mutated Measles Virus Matrix and Fusion Protein Influence Viral Titer In Vitro and Neuro-Invasion in Lewis Rat Brain Slice Cultures

Viruses ◽  
2021 ◽  
Vol 13 (4) ◽  
pp. 605
Author(s):  
Johannes Busch ◽  
Soroth Chey ◽  
Michael Sieg ◽  
Thomas W. Vahlenkamp ◽  
Uwe G. Liebert
Keyword(s):  
Fusion Protein ◽  
Rat Brain ◽  
Measles Virus ◽  
Brain Slice ◽  
Matrix Protein ◽  
Brain Slices ◽  
Vero Cells ◽  
Viral Spread ◽  
Brain Slice Cultures ◽  
Rat Brain Slice

Measles virus (MV) can cause severe acute diseases as well as long-lasting clinical deteriorations due to viral-induced immunosuppression and neuronal manifestation. How the virus enters the brain and manages to persist in neuronal tissue is not fully understood. Various mutations in the viral genes were found in MV strains isolated from patient brains. In this study, reverse genetics was used to introduce mutations in the fusion, matrix and polymerase genes of MV. The generated virus clones were characterized in cell culture and used to infect rat brain slice cultures. A mutation in the carboxy-terminal domain of the matrix protein (R293Q) promoted the production of progeny virions. This effect was observed in Vero cells irrespective of the expression of the signaling lymphocyte activation molecule (SLAM). Furthermore, a mutation in the fusion protein (I225M) induced syncytia formation on Vero cells in the absence of SLAM and promoted viral spread throughout the rat brain slices. In this study, a solid ex vivo model was established to elucidate the MV mutations contributing to neural manifestation.

Neuronal activity evaluated by the uptake of [18F]FDG in rat brain slices

1998 ◽  
Vol 31 ◽  
pp. S134
Author(s):  
S. Yoshida ◽  
T. Murata ◽  
N. Omata ◽  
H. Oka ◽  
Y. Yonekura
Keyword(s):  
Rat Brain ◽  
Neuronal Activity ◽  
Brain Slices ◽  
18F Fdg

Effect of anoxia on excitatory amino acids in brain slices of rats and turtles: in vitro microdialysis

1993 ◽  
Vol 264 (4) ◽  
pp. R716-R719 ◽  
Author(s):  
R. S. Young ◽  
M. J. During ◽  
D. F. Donnelly ◽  
W. J. Aquila ◽  
V. L. Perry ◽  
...  
Keyword(s):  
Amino Acids ◽  
Rat Brain ◽  
Excitatory Amino Acids ◽  
Brain Slice ◽  
Brain Slices ◽  
Oxygen Deprivation ◽  
Adult Rat ◽  
The Difference ◽  
Rat Brain Slice

Using in vitro microdialysis, we tested the hypothesis that anoxia-induced release of excitatory amino acids is greater in adult rat brain than in turtle brain. Ten minutes of anoxia produced significant elevation of glutamate (from 0.39 +/- 0.03 to 0.90 +/- 0.18 microM dialysate, means +/- SE, P < 0.05), aspartate (from 0.28 +/- 0.12 to 1.20 +/- 0.49 microM, P < 0.05), glycine, and alanine in the rat brain slice. During reoxygenation, alanine and glycine returned toward baseline values, whereas aspartate and glutamate remained elevated. In contrast, prolonged anoxia (60 min) in the turtle brain slice resulted in only minimal increase in aspartate (from 0.06 +/- 0.01 to 0.09 +/- 0.02 microM, P < 0.05) and, interestingly, a decrease in glutamate (from 0.50 +/- 0.11 to 0.33 +/- 0.09 microM, P < 0.05). Levels of glycine, alanine, and taurine were unchanged. We conclude that oxygen deprivation causes marked increase in excitatory amino acids in the anoxia-sensitive rat brain slice, while oxygen deprivation for an even longer period of time in the turtle brain slice produces substantially less change. We speculate that the difference in sensitivity to anoxia between rat and turtle is at least partly attributable to the major difference in interstitial levels of excitotoxic amino acids during oxygen deprivation.

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