Rabbit Brain Research Articles

Oxidative stress markers in brain and gonads of rabbit bucks fed herbal supplements

BackgroundCurrently, there is an increase in the usage of phytogenic feed additives to help improve animal welfare and productivity, while less emphasis is now placed on metabolic and oxidative stability of neuronal and testicular tissues. This study aims at investigating the effects of Moringa oleifera, Phyllanthus amarus and Viscum album as feed additives on some metabolic indicators and oxidative status of rabbit testis and brain. Isonitrogenous and isocaloric diets were formulated with 5% supplementation of each of the phytogenic additive to 3 treatment groups and basal diet group.ResultsIt was revealed that moringa, mistletoe, and phyllanthus can modulate oxidative status in both the brain and gonads of rabbit bucks through their unique phytochemical compositions, thereby affecting reproductive and cognitive functions. Moringa, rich in crude protein, saponins, glycosides, and steroids, enhances protein and lactate dehydrogenase levels but increases lipid peroxidation in the testis. Mistletoe, with high crude fiber, ash, and antioxidants like flavonoids and tannins, boosts total antioxidant activity in several brain regions and reduces lipid peroxidation, indicating its potential for reducing oxidative stress. Phyllanthus, having the least fiber and ash but effective antioxidant properties, notably affects the oxidative balance in both the testis and brain, with varied impacts on different tissues. The result obtained showed that total antioxidant activity of the left testis was enhanced (p < 0.05) by inclusion of the phytogenic additives, while total antioxidant activity of the right testis in bucks fed on phytogenic additives were similar (p > 0.05) to bucks on basal diet. Bucks fed on moringa and phyllanthus additives had higher (p < 0.05) testicular lipid peroxidation, lowered testicular protein and/or lactate dehydrogenase. Result also shows that lipid peroxidation of hypothalamus, cerebrum, olfactory lobe and cerebellum were lowest in bucks fed on mistletoe, phyllanthus, phyllanthus and phyllanthus, respectively. High catalase activity of optic lobe, olfactory lobe and cerebellum were observed in bucks fed on mistletoe, moringa and mistletoe, respectively, while glutathione peroxidase activity in hypothalamus, cerebrum, olfactory lobe and pineal was enhanced (p < 0.05) in bucks fed on moringa and mistletoe compared to bucks on other treatment.ConclusionM. oleifera, P. amarus and V. album leaves as phytogenic feed additives in rabbit diets have negative effect on the metabolic activity of the testis, enhancing antioxidant activity in the brain.

Effect of Dietary Tigernut on Acetylcholinesterase, Specific Acetylcholinester, and Total Protein Levels in Rabbit Brains of Different Genotupes

Effect of Dietary Tigernut on Acetylcholinesterase, Specific Acetylcholinester, and Total Protein Levels in Rabbit Brains of Different Genotupes

Preparation, characterisation, pharmacokinetics and distribution of esculin microspheres administered via intravitreal injection into rabbit brain

This study explored the distribution of esculin microspheres in rabbit brain tissue following intravitreal injection and investigated the possibility of direct entry of the drug into the brain through the eye, to develop a formulation with enhanced therapeutic efficacy against Parkinson’s disease. Chitosan microspheres of esculin were prepared via an emulsification cross-linking method and their characteristics were evaluated, including angle of repose, bulk density, and swelling ratio. Furthermore, the pharmacokinetic parameters and brain tissue distribution in rabbits were compared among groups administered esculin eye drops, intravitreal esculin solution, and intravitreal esculin microspheres, to determine whether esculin could enter the brain through an ocular route. The results showed that the prepared esculin microspheres were spherical and had good fluidity. Notably, intravitreal administration enhanced the area under the curve (AUC) of esculin in the thalamus. Delivery through microspheres prolonged the drug retention time in both rabbit plasma and brain tissues, as well as the brain-targeting efficiency of esculin. The collective findings indicated that there may be a direct eye-brain pathway facilitating enter of esculin microspheres into brain tissue after intravitreal injection, supporting the utility of intravitreal esculin microspheres as an effective therapeutic formulation for Parkinson’s disease, a long-term chronic condition.

Retraction to: Potential Mechanisms Linking Cholesterol to Alzheimer's Disease-like Pathology in Rabbit Brain, Hippocampal Organotypic Slices, and Skeletal Muscle.

Retraction to: Potential Mechanisms Linking Cholesterol to Alzheimer's Disease-like Pathology in Rabbit Brain, Hippocampal Organotypic Slices, and Skeletal Muscle.

The Erratic History of Electroencephalography

The history of electroencephalography begins around 1850 with a supposition of Emil du Bois-Reymond concerning the transfer of information by electric currents over the nerve to the effector. Luigi Galvani in Bologna showed with his frog legs experiments 1786 indeed the existence of animal electricity. Richard Caton in Liverpool placed in 1875 as the first electrodes on the brains of rabbits and was able to record the electrical brain activity. Caton received little attention for his research and left with his animal experiment aversion the field. In contrast to Caton, Adolf Beck in Kraków, got a huge attention for his recordings of the electrical activities of the frog brain. The most interesting response to his important paper of 1890 came from Vasili Danilewski from Charkov, mentioning his unpublished doctoral thesis of 1877. He did his dog recordings before Beck, but one year after Caton who send him his abstract, remaining that he discovered before him electric brain waves. Colleagues of Danilewski such as Práwdicz- Neminski from Kyiv performed also adequate work in this field, but due to Stalin's dogmatic regime, electrophysiology became prohibited and disappeared in Russian. Jewish Adolf Beck, now professor in Lwów, experienced there in war time in 1940 dangerous times and ultimately the Nazi’s came for him. His son succeeded to hand him a cyanide capsule to save him from the gas chamber. By the tragedies of the war in Poland and the split between East and West Europe, Beck and his work go lost. Hans Berger began in Jena with brain recordings in humans and in 1927 he exclaimed ‘I can record brain actvity from an intact human skull’. This was replicated abd agreed upon by Edgar Adrian in 1934, and Berger received international fame, but not in Germany. The often authoritative Berger hated the Nazi’s and was suspended by the regime. He came in a severe depression and ended his life by hanging in June 1941. In this heavy war time, electrophysiology moved to the USA. Frederic and Erna Gibbs at Harvard got, with their studies of epilepsy in 1934 a breakthrough in clinical electroencephalography, Alfred Loomis and Herbert Jasper used the electrical brain actvity to identify several stages of sleep. Later, Jasper performed in Montreal, with neurosurgeon Wilder Penfield, important research on focal epilepsies. After the second world war, around 1950, electroencephalography blossomed up, in the USA as well as in Europe. Recording electroencephalograms for studying the functioning of the brain and in particular investigating domains of sleep and epilepsy. It became common that almost every university and hospital had a resording device. That electroencephalography was a mature methodology, was demonstrated by great discoveries for example through the finding of REM sleep by Kleitman and Aserinski in 1953.

Long-term pulmonary and neurodevelopmental impairment in a fetal growth restriction rabbit model.

Fetal growth restriction (FGR) remains one of the main obstetrical problems worldwide, with consequences beyond perinatal life. Animal models with developmental and structural similarities to the human are essential to understand FGR long-term consequences and design novel therapeutic strategies aimed at preventing or ameliorating them. Herein, we described the long-term consequences of FGR in pulmonary function, structure, and gene expression, and characterized neurodevelopmental sequelae up to preadolescence in a rabbit model. FGR was induced at gestational day 25 by surgically reducing placental blood supply in one uterine horn, leaving the contralateral horn as internal control. Neonatal rabbits born near term were assigned to foster care in mixed groups until postnatal day (PND) 21. At that time, one group underwent pulmonary biomechanical testing followed by lung morphometry and gene expression analysis. A second group underwent longitudinal neurobehavioral assessment until PND 60 followed by brain harvesting for multiregional oligodendrocyte and microglia quantification. FGR was associated with impaired pulmonary function and lung development at PND 21. FGR rabbits had higher respiratory resistance and altered parenchymal biomechanical properties in the lungs. FGR lungs presented thicker alveolar septal walls and reduced alveolar space. Furthermore, the airway smooth muscle content was increased, and the tunica media of the intra-acinar pulmonary arteries was thicker. In addition, FGR was associated with anxiety-like behavior, impaired memory and attention, and lower oligodendrocyte proportion in the frontal cortex and white matter. In conclusion, we documented and characterized the detrimental pulmonary function and structural changes after FGR, independent of prematurity, and beyond the neonatal period for the first time in the rabbit model, and describe the oligodendrocyte alteration in pre-adolescent rabbit brains. This characterization will allow researchers to develop and test therapies to treat FGR and prevent its sequelae.

Sub-aperture ultrafast volumetric ultrasound imaging for fully sampled dual-mode matrix array

Fully sampled dual-mode matrix array ultrasound transducer is capable of performing imaging and therapeutic ultrasound in three dimensions (3D). It is a promising tool for many clinical applications because of its precise multi-focus therapy with imaging guidance by itself. Our team previously designed a 256-element fully sampled dual-mode matrix array transducer, while its imaging quality needs to be further improved. In this work, we propose a high-contrast sub-aperture volumetric imaging strategy to improve the imaging quality of the dual-mode matrix array. We first analyzed the effect of various parameters of sub-aperture imaging on the imaging quality by Field II. Based on the optimized parameters, we compared the resolution and signal to noise ratio (SNR) of sub-aperture imaging with those of full aperture imaging on phantoms and rabbit brain. The experimental results showed the proposed sub-aperture imaging method could obtain a comparable resolution to full aperture imaging. Moreover, the average intensity of noise signal near the wire phantom decreased by about 5 dB and the SNR of tissue phantom image increased by 8 %. The proposed sub-aperture imaging method also enabled clearer and more accurate imaging of the rabbit brain. The obtained results indicate the proposed sub-aperture imaging is a promising method for practical use of a fully sampled dual-mode matrix array for volumetric ultrasound imaging.

Neutralizing RGMa with Elezanumab Promotes Cerebroprotection and Recovery in Rabbit Middle Cerebral Artery Occlusion

Repulsive guidance molecule A (RGMa) is an inhibitor of neuronal growth and survival which is upregulated in the damaged central nervous system following acute spinal cord injury (SCI), traumatic brain injury, acute ischemic stroke (AIS), and other neuropathological conditions. Neutralization of RGMa is neuroprotective and promotes neuroplasticity in several preclinical models of neurodegeneration and injury including multiple sclerosis, AIS, and SCI. Given the limitations of current treatments for AIS due to narrow time windows to intervention (TTI), and restrictive patient selection criteria, there is significant unmet need for therapeutic agents that enable tissue survival and repair following acute ischemic damage for a broader population of stroke patients. In this preclinical study, we evaluated whether elezanumab, a human anti-RGMa monoclonal antibody, could improve neuromotor function and modulate neuroinflammatory cell activation following AIS with delayed intervention times up to 24 h using a rabbit embolic permanent middle cerebral artery occlusion model (pMCAO). In two replicate 28-day pMCAO studies, weekly intravenous infusions of elezanumab, over a range of doses and TTIs of 6 and 24 h after stroke, significantly improved neuromotor function in both pMCAO studies when first administered 6 h after stroke. All elezanumab treatment groups, including the 24 h TTI group, had significantly less neuroinflammation as assessed by microglial and astrocyte activation. The novel mechanism of action and potential for expanding TTI in human AIS make elezanumab distinct from current acute reperfusion therapies, and support evaluation in clinical trials of acute CNS damage to determine optimal dose and TTI in humans.Graphical A: Ramified/resting astrocytes and microglia in a normal, uninjured rabbit brain. B: Rabbit pMCAO brain illustrating lesion on right side of brain (red), surrounded by penumbra (pink) during acute phase post stroke, with minimal injury to left brain hemisphere. Penumbra characterized by activated astrocytes and microglia (region in crosshair within circle), with upregulation of free and bound RGMa. C: Elezanumab binds to both free and bound RGMa, preventing full activation of astrocytes and microglia. D: Elezanumab is efficacious in rabbit pMCAO with a 4 × larger TTI window vs. tPA (6 vs. 1.5 h, respectively). In human AIS, tPA is approved for a TTI of 3-4.5 h. Elezanumab is currently being evaluated in a clinical Ph2 study of AIS to determine the optimal dose and TTI (NCT04309474).

The proteasome interactome and its role in the mechanisms of brain plasticity

Proteasomes are highly conserved multienzyme complexes responsible for the proteolytic degradation of short-lived, regulatory, misfolded, and damaged proteins. They play an important role in the processes of brain plasticity, and the decrease in their function is accompanied by the development of neurodegenerative pathology. Studies performed in different laboratories both on cultured mammalian and human cells and on preparations of the rat and rabbit brain cortex revealed a large number of proteasome-associated proteins. Since the identified proteins belong to certain metabolic pathways, multiple enrichment of the proteasome fraction with these proteins indicates their important role the proteasome functioning. Extrapolation of the experimental data, obtained on various biological objects, to the human brain, suggests that proteasome-associated proteins account for at least 28% of the human brain proteome. The proteasome interactome of the brain contains a large number of proteins involved in the assembly of these supramolecular complexes, regulation of their functioning, and intracellular localization, which can be changed at different conditions (for example, during oxidative stress) or in different phases of the cell cycle. In the context of the molecular functions of the Gene Ontology (GO) Pathways, the proteins of the proteasome interactome mediate cross-talk between components of more than 30 metabolic pathways annotated in terms of GO. The main result of these interactions is the binding of adenine and guanine nucleotides, crucial for realization of the nucleotide-dependent functions of the 26S and 20S proteasomes. Since the development of neurodegenerative pathology is often associated with a regioselective decrease in the functional activity of proteasomes, a positive therapeutic effect will obviously be provided by factors increasing the proteasomal activity. In any case, the pharmacological regulation of brain proteasomes seems to be realized through changes in the composition and/or activity of proteins associated with proteasomes (deubiquitinase, PKA, CaMKIIα, etc.).

Oxytocin antagonist does not disrupt rabbit maternal behavior despite binding to brain oxytocin receptors.

We explored a possible role of oxytocin (OXT) for the onset and maintenance of rabbit maternal behavior by: (a) confirming that a selective oxytocin receptor antagonist (OTA) widely used in rodents selectively binds to OXT receptors (OXTR) in the rabbit brain and (b) determining the effect of daily intracerebroventricular (icv) injections of OTA to primiparous and multiparous does from gestation day 29 to lactation day 3. OTA efficiently displaced the high affinity, selective oxytocin receptor (OXTR) radioligand, 125 I-labeled ornithine vasotocin analog (125 I-OVTA), but was much less effective at displacing the selective V1a vasopressin receptor radioligand, 125 I-labeled linear vasopressin, thus showing high affinity and selectivity of OTA for rabbit OXTR as in rodents. Further, ICV OTA injections did not modify nest-building, latency to enter the nest box, time spent nursing or the amount of milk produced, relative to vehicle-injected does. The percentage of mothers suckling the litter was also similar between both groups, regardless of parity. Together, our results do not support a role of OXT for the initiation or maintenance of rabbit maternal behavior. Future studies are warranted to determine if OXT participates in fine-tuning additional aspects of the maternal ethogram, for example, circadian periodicity of nursing and nest defense.

Influence of α&lt;sub&gt;2&lt;/sub&gt;-Adrenoreceptor Antagonists on Electroencephalogram Characteristics after Dexmedetomidine Administration in Rabbits

The humane treatment of laboratory animals is an integral part of good laboratory practice. It remains relevant to study the anaesthetic effects of various medicinal products helping to reduce pain and distress in laboratory animals.The aim of the study was to compare the effects of the α2 blockers proroxan and atipamezole on changes in electroencephalogram rhythm index ratios after dexmedetomidine administration.Materials and methods. The study used male Soviet chinchilla rabbits weighing 3.0±0.3 kg (n=12). Study animals received single injections of 100 μg/kg dexmedetomidine subcutaneously, 50 μg/kg atipamezole intramuscularly, and 170 μg/kg proroxan intravenously (equimolar to the dose of dexmedetomidine). The effects of these medicinal products were evaluated by pharmacoelectroencephalography. The authors recorded electroencephalograms using cup electrodes and a Neuron-Spectrum-1 8-channel encephalograph (Neurosoft, Russia) with a bandwidth of 0.5–35 Hz and a sampling frequency of 500 Hz. The distribution of quantitative characteristics was checked for normality using the Shapiro–Wilk W test. The authors used one-way ANOVA with Dunnett’s post hoc test to evaluate the significance of differences for the normal distribution of quantitative characteristics; they used the nonparametric Kruskal–Wallis test with Dunn’s post hoc test for the non-normal one.Results. Dexmedetomidine administration resulted in significant two-hour changes in the rabbit brain, and the authors observed an increase in the delta rhythm and a decrease in the theta rhythm. At equimolar doses, atipamezole returned the ratios of the wave rhythm indices to the baseline values, whereas proroxan had no effect on the ratios.Conclusions. As demonstrated by the neutralisation of dexmedetomidine sedative and hypnotic effects, atipamezole can be used in veterinary for recovery from anaesthesia. Proroxan, on the contrary, is not effective in reversing the sedative effect of dexmedetomidine.

The BCO2 Genotype and the Expression of BCO1, BCO2, LRAT, and TTPA Genes in the Adipose Tissue and Brain of Rabbits Fed a Diet with Marigold Flower Extract.

This study was undertaken to evaluate the effect of the BCO2 genotype and dietary supplementation with marigold flower extract on the expression of BCO1, BCO2, LRAT, and TTPA genes in the adipose tissue and brain of rabbits. The concentrations of lutein, zeaxanthin, β-carotene, retinol, and α-tocopherol were determined in samples collected from rabbits. Sixty young male Termond White rabbits were allocated to three groups based on their genotype at codon 248 of the BCO2 gene (ins/ins, ins/del, and del/del). Each group comprised two subgroups; one subgroup was administered a standard diet, whereas the diet offered to the other subgroup was supplemented with 6 g/kg of marigold flower extract. The study demonstrated that the BCO2 genotype may influence the expression levels of the BCO2, LRAT, and TTPA genes in adipose tissue, and TTPA and BCO1 genes in the brain. Moreover, an increase in the amount of lutein in the diet of BCO2 del/del rabbits may increase the expression of BCO1, LRAT, and TTPA genes in adipose tissue, and the expression of the BCO2 gene in the brain. Another finding of the study is that the content of carotenoids and α-tocopherol increases in both the adipose tissue and brain of BCO2 del/del rabbits.

Phenotyping of Macrophages After Radiolabeling and Safety of Intra-arterial Transplantation Assessed by SPECT/CT and MRI

Cell therapy is an integral modality of regenerative medicine. Macrophages are known for their sensitivity to activation stimuli and capability to recruit other immune cells to the sites of injury and healing. In addition, the route of administration can impact engraftment and efficacy of cell therapy, and modern neuro-interventional techniques provide the possibility for selective intra-arterial (IA) delivery to the central nervous system (CNS) with very low risk. The effects of radiolabelling and catheter transport on differentially activated macrophages were evaluated. Furthermore, the safety of selective IA administration of these macrophages to the rabbit brain was assessed by single-photon emission computed tomography/computed tomography (SPECT/CT) and ultra-high-field (9.4 T) magnetic resonance imaging (MRI). Cells were successfully labeled with (111In)In-(oxinate)3 and passed through a microcatheter with preserved phenotype. No cells were retained in the healthy rabbit brain after IA administration, and no adverse events could be observed either 1 h (n = 6) or 24 h (n = 2) after cell administration. The procedure affected both lipopolysaccharide/gamma interferon (LPS/IFNγ) activated cells and interleukin 4 (IL4), interleukin 10 (IL10)/transforming growth factor beta 1 (TGFβ1) activated cells to some degree. The LPS/IFNγ activated cells had a significant increase in their phagocytotic function. Overall, the major impact on the cell phenotypes was due to the radiolabeling and not passage through the catheter. Unstimulated cells were substantially affected by both radiolabeling and catheter administration and are hence not suited for this procedure, while both activated macrophages retained their initial phenotypes. In conclusion, activated macrophages are suitable candidates for targeted IA administration without adverse effects on normal, healthy brain parenchyma.

Development of Rabbit Brain Tumor Model Using VX2 Cells and Verification with the MRI in Neuroradiologic Research

To evaluate the development, location, and volume of a VX2 carcinoma using four inoculation methods in a rabbit brain. Inoculation of a VX2 cell suspension was performed 1) on the appointed day, 2) seven days after storing a VX2 carcinoma in a freezer or 3) seven days after storing a VX2 carcinoma in a deep freezer after sacrificing the donor rabbits. 4) Without sacrificing the rabbits, the VX2 cell suspension was obtained using a gun biopsy, inoculation was performed on the appointed day. MR imaging was performed 10 days after inoculation. Brain tissues were obtained the day after. The development, location, and volume of the tumor were evaluated. Seventeen of the 18 rabbits inoculated on the appointed day developed tumors (average tumor volume, 106.32 mm3). One of five inoculated seven days after storing the VX2 tumor in the freezer, and three of five inoculated seven days after storing the VX2 tumor in the deep freezer developed tumors. Inoculation with a VX2 cell suspension obtained with a gun biopsy from five rabbits revealed development of tumors in only two rabbits. The tumors mostly developed in the superficial cortex. TVX2 rabbit brain tumor model is easy to develop and revealed variable reproducibility. This model can be applicable in radiologic imaging, treatment planning, interventional treatment and drug delivery research. VX2 cell can be successfully innoculated into the brain using variable methods under researcher's variable conditions.

Delineation of the healthy rabbit heart by immunohistochemistry – A technical note

Heart failure poses a big health problem and may result from obesity, smoking, alcohol and/or growing age. Studying pathological heart tissue demands accurate histological and immunohistochemical stainings in animal models, including chromogenic and fluorescent approaches. Moreover, a reliable set of healthy heart stainings and labeling are required, in order to provide a reference for the pathological situation. Heart and brain tissue of a healthy rabbit were collected, and different histological key steps were compared, such as paraffin embedding after formalin fixation versus cryopreservation; an antigen retrieval (AR) step in processing paraffin sections versus the same procedure without AR; or a chromogenic with a fluorescent detection system, respectively. Using serial sections, we stained the same morphological structure with classic approaches (HE, Masson Goldner Trichrome (GT) and Elastica van Gieson (EL)) and with different markers, including collagen I, collagen III, fibronectin, α-SMA, protease-activated receptor-2 (PAR-2) which is an inflammation-related marker, and ki67 for proliferating cells. Differences between conditions were quantitatively assessed by measuring the color intensity. Generally, cryosections exhibited a more prominent signal intensity in immunohistochemically labeled sections than in paraffin sections, but the strong staining was slurry, which sometimes impeded proper identification of morphological structures, particularly at higher magnifications. In addition, the advantage of an AR step was observed when compared to the condition without AR, where signal intensities were significantly lower. Different stainings of the heart arteries and the myocardium revealed a clear distribution of extracellular matrix components, with prominent collagen III in the artery wall, but an absence of collagen III in the myocardium. Moreover, paraffin-embedded sections provided more distinct structures compared to cryosections after collagen III, ki67, fibronectin, and α-SMA labeling. As for the Purkinje cells that were depicted in the heart and the cerebellum (Purkinje neurons), we found GT staining most suitable to depict them in the heart, while HE as well as EL staining was ideal to depict Purkinje neurons in the cerebellum. In sum, we provide useful reference images with different stainings for researchers using the rabbit heart or brain model. Such images can help to decide which of the immunohistochemical protocols are valuable to reach a specific aim. Recommendations are given for the best visualization of the target structures and specific (immunohistochemical) staining.

A pilot study of contrast-enhanced electrical impedance tomography for real-time imaging of cerebral perfusion.

Real-time detection of cerebral blood perfusion can prevent adverse reactions, such as cerebral infarction and neuronal apoptosis. Our previous clinical trial have shown that the infusion of therapeutic fluid can significantly change the impedance distribution in the brain. However, whether this alteration implicates the cerebral blood perfusion remains unclear. To explore the feasibility of monitoring cerebral blood perfusion, the present pilot study established a novel cerebral contrast-enhanced electrical impedance tomography (C-EIT) technique. Rabbits were randomly divided into two groups: the internal carotid artery non-occlusion (ICAN) and internal carotid artery occlusion (ICAO) groups. Both of groups were injected with glucose, an electrical impedance-enhanced contrast agent, through the right internal carotid artery under EIT monitoring. The C-EIT reconstruction images of the rabbits brain were analyzed according to the collected raw data. The paired and independent t-tests were used to analyze the remodeled impedance values of the left and right cerebral hemispheres within and between studied groups, respectively. Moreover, pathological examinations of brain were performed immediately after C-EIT monitoring. According to the reconstructed images, the impedance value of the left cerebral hemisphere in the ICAN group did not change significantly, whereas the impedance value of the right cerebral hemisphere gradually increased, reaching a peak at approximately 10 s followed by gradually decreased. In the ICAO group, the impedance values of both cerebral hemispheres increased gradually and then began to decrease after reaching the peak value. According to the paired t-test, there was a significant difference (P < 0.001) in the remodeling impedance values between the left and right hemispheres in the ICAN group, and there was also a significant difference (P < 0.001) in the ICAO group. According to the independent t-test, there was a significant difference (P < 0.001) of the left hemispheres between the ICAN and ICAO groups. The cerebral C-EIT proposed in this pilot study can reflect cerebral blood perfusion. This method has potential in various applications in the brain in the future, including disease progression monitoring, collateral circulation judgment, tumor-specific detection, and brain function research.

Abstract 112: A Transcriptomic Evaluation Of Brain And Cardiac Tissues After Cardiac Arrest In Rabbits

Introduction: A sepsis-like syndrome is known to occur rapidly after cardiac arrest. Hypothesis: A comprehensive investigation of immune signaling pathways could allow a better understanding or brain and heart disorders after cardiac arrest in rabbits. Methods: Anesthetized rabbits underwent 10 min of ventricular fibrillation. After resuscitation, they were followed during 2 or 6 h before brain and heart withdrawal (n=6 in each condition). Additional animals were submitted to a Sham procedure (n=6). The transcriptome was sequenced in cerebral and cardiac samples. Long mRNA expression was quantified vs Sham (fold-change &gt; 1.5; p&lt;0.05) before functional enrichment for pathways analysis using Reactome ID (R-HSA-9014325). Results: 403 and 1561 genes were differentially expressed at 2 and 6 h in the brain of rabbits submitted to cardiac arrest vs Sham, respectively. Those genes related to 233 and 104 signaling pathways at 2 and 6 h, among which 15 and 1 concerned innate immunity or inflammation pathways, respectively (Table). This included several pathways related to interleukins (IL-1, 4&amp;13 and 17) and toll-like receptors (TLR-1, 2, 6 and 9). In the heart, 1786 and 1457 genes were differentially expressed at 2 and 6 after cardiac arrest vs Sham. These genes were related to 68 and 58 signaling pathways at 2 and 6 h, among which only 1 and 3 concerned immunity or inflammation, respectively. Conclusion: Immuno-inflammatory events appears rapidly after cardiac arrest in the brain, supporting the need for early intervention to prevent neuro-inflammatory events. Conversely, the immuno-inflammatory response do not seem critical in the heart in the early phase after cardiac arrest. Table 1: p values of immune pathways significantly altered in either brain or heart after 2 or 6 hours after cardiac arrest, as compared to Sham animals.

Postmortem Distribution and Postmortem Redistribution of Carbofuran-7-Phenyl Glucuronic Acid in Rabbits.

To establish a carbofuran intragastric administration death model in rabbits, and to observe the postmortem distribution and postmortem redistribution of carbofuran-7-phenyl glucuronic acid (Glu-7PH) in rabbits. The postmortem distribution: Rabbits were given an administration of 1/2LD50, LD50, 2LD50 carbofuran. Dead rabbits were dissected immediately. Rabbits that had remained alive 2 hours were sacrificed by carbon dioxide (CO2) inhalation and dissected immediately. The myocardium, cardiac blood, liver, spleen, lung, kidney, brain and right hindlimb muscle were collected. The postmortem redistribution: After giving an administration of 4LD50 carbofuran, the myocardium, cardiac blood, liver, spleen, lung, kidney, brain, and right hindlimb muscle were collected at 0, 12, 24, 48, and 72 h postmortem in supine position at 15 ℃ room temperature. The quantity of Glu-7PH was determined by LC-MS/MS. The postmortem distribution: Among the three dose groups, there were significant differences in the quantities of Glu-7PH in different tissues. The postmortem redistribution: There was no significant difference in the Glu-7PH quantities in cardiac blood, mycardium, spleen, kidney, brain and right hindlimb muscle, but there was a significant difference in the Glu-7PH quantities in the liver and lung. The mycardium, cardiac blood, liver, lung, kidney, brain and hindlimb muscle of rabbits can be used as appropriate samples for Glu-7PH detection. However, it should be noted that Glu-7PH was redistributed postmortem in rabbit liver and lung.

Large-volume and deep brain imaging in rabbits and monkeys using COMPACT two-photon microscopy

In vivo imaging has been widely used for investigating the structure and function of neurons typically located within ~ 800 μm below the cortical surface. Due to light scattering and absorption, it has been difficult to perform in-vivo imaging of neurons in deep cortical and subcortical regions of large animals with two-photon microscopy. Here, we combined a thin-wall quartz capillary with a GRIN lens attached to a prism for large-volume structural and calcium imaging of neurons located 2 mm below the surface of rabbit and monkey brains. The field of view was greatly expanded by rotating and changing the depth of the imaging probe inside a quartz capillary. Calcium imaging of layer 5/6 neurons in the rabbit motor cortex revealed differential activity of these neurons between quiet wakefulness and slow wave sleep. The method described here provides an important tool for studying the structure and function of neurons located deep in the brains of large animals.

Comparative Analysis of Proteins Associated with 26S and 20S Proteasomes Isolated from Rabbit Brain and Liver

Comparative Analysis of Proteins Associated with 26S and 20S Proteasomes Isolated from Rabbit Brain and Liver