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Anna Janecka - One of the best experts on this subject based on the ideXlab platform.

  • Effect of tooth pulp and periaqueductal central gray electrical stimulation on β-endorphin release into the fluid perfusing the Cerebral Ventricles in rats
    Brain Research, 2011
    Co-Authors: Maria Zubrzycka, Anna Janecka
    Abstract:

    Abstract Our previous studies demonstrated that tooth pulp stimulation increases the pain threshold, whereas stimulation of the periaqueductal central gray (PAG) has the opposite effect. The aim of this study was to investigate the effect exerted by electrical stimulation of the nociceptive afferent terminals in the tooth pulp and analgesic electrical stimulation of the PAG on the release of immunoreactive β-endorphin (β-EP-IR) into the cerebrospinal fluid (CSF) and artificial cerebrospinal fluid (aCSF) perfusing the Cerebral Ventricles in rat, and to establish whether during such stimulation the μ-opioid receptor (MOR) was activated. The tongue jerk reflex was induced by dental pulp stimulation in rats under chloralose anesthesia. CSF was collected from the cerebello-medullary cistern, and then 30-minute perfusions of the lateral Ventricles with aCSF were conducted with collection of perfusate portions from the cerebello-medullary cistern at rest (control), during electrical tooth pulp stimulation evoking the nociceptive tongue jerk reflex and during inhibition of that reflex with simultaneous stimulation of tooth pulp and the PAG. In the second series of experiments, a MOR-selective antagonist, β-funaltrexamine (β-FNA) was perfused through the Cerebral Ventricles 10 min before tooth pulp stimulation. β-EP-IR was determined in the collected CSF and aCSF perfusates by radioimmunoassay (RIA). Stimulation of tooth pulp with electrical impulses resulted in a significant increase of β-EP-IR. On the other hand, simultaneous tooth pulp and PAG stimulation inhibited β-EP-IR release into the fluid perfusing the Cerebral Ventricles. β-FNA blocked evoked tongue jerks (ETJ) induced by PAG stimulation, but no enhancing effect of β-FNA on β-EP-IR release into the perfusate was observed. The obtained results indicate that stimulation of the tooth pulp increases β-EP release significantly, whereas PAG stimulation significantly inhibits β-EP-IR release into the CSF, and that these effects are mediated by MOR. The results of the experiments allow to conclude that endogenous β-EP, released as a result of electrical tooth pulp stimulation in orofacial pain, diffuses through the cerebroventricular ependyma into the CSF and exerts a modulatory effect, mediated by MOR, alterating the properties of neurons in the trigeminal sensory nuclei, interneurons, and motoneurons of the hypoglossal nerve.

  • Substance P content in the cerebrospinal fluid and fluid perfusing Cerebral Ventricles during elicitation and inhibition of trigemino-hypoglossal reflex in rats
    Brain Research, 2002
    Co-Authors: Maria Zubrzycka, Anna Janecka
    Abstract:

    The aim of this study was to establish whether tooth pulp and periaqueductal central gray (PAG) stimulation affects the release of substance P (SP) into the fluid perfusing the Cerebral Ventricles in rats. The content of substance P in the cerebrospinal fluid and fluid perfusing Cerebral Ventricles was determined during incisor pulp stimulation with electrical impulses inducing nociceptive trigemino-hypoglossal reflex and then during inhibition of the reflex by stimulation of PAG. Perfusion of the Cerebral Ventricles was carried out using artificial cerebrospinal fluid (aCSF). SP-like immunoreactivity (SP-LI) was determined in the samples by radioimmunoassay. Samples were collected in four groups: first group-cerebrospinal fluid (CSF); second group-aCSF perfusates without stimulation; third group-aCSF perfusates during incisor pulp stimulation; fourth group-aCSF perfusates during incisor pulp stimulation and simultaneous inhibition of trigemino-hypoglossal reflex by PAG stimulation. It was shown that incisor pulp stimulation led to the increased release of SP-LI into the fluid perfusing Cerebral Ventricles. Stimulation of PAG reduced the release of SP-LI into the cerebro-ventricular system to the values obtained before the tooth pulp stimulation. The results indicate that PAG significantly inhibits the release of SP-LI into the rat Cerebral ventricular system and may be involved in the inhibition of trigemino-hypoglossal reflex.

  • comparison of antagonistic properties of substance p analogs spantide i ii and iii on evoked tongue jerks in rats
    Endocrine Regulations, 2000
    Co-Authors: Maria Zubrzycka, Anna Janecka, Wladyslaw Z Traczyk
    Abstract:

    OBJECTIVE: To study and evaluate the effects of perfusion through Cerebral Ventricles with substance P (SP) and its analogs: spantide I, II and III on evoked tongue jerks (ETJ) in male rats. METHODS: During the perfusion, stimulation of the tooth pulp caused retractive movements of the stretched tongue, the amplitudes of which were recorded. The mean amplitudes of evoked tongue jerks (ETJ) recorded during each 10 min. period of perfusion with McIlwain-Rodnight's solution and solutions containing peptides were compared. RESULTS: Perfusion of Cerebral Ventricles with SP caused a significant increase in the mean amplitude of evoked tongue jerks. Spantide I caused a complete respiratory arrest in all of the examined animals, so its effect on the trigemino-hypoglossal reflex could not have been tested. Spantide II, in the first two minutes, induced a transient significant decrease in ETJ amplitude, followed by an increase in ETJ in the next 8 min. SP perfused after spantide II caused a further significant increase in ETJ, as compared with control. Perfusion of Cerebral Ventricles with spantide III caused a significant, dose-dependent decrease in ETJ. SP perfused after spantide III caused a smaller increase in ETJ than it was observed without spantide III. CONCLUSION: Spantide III was found to be a strong antagonist of SP in trigemino-hypoglossal reflex.

  • inhibition of tongue reflex in rats by tooth pulp stimulation during Cerebral ventricle perfusion with 6 11 substance p analogs
    Brain Research, 1997
    Co-Authors: Maria Zubrzycka, Anna Janecka, Wiktor Koziolkiewicz, Wladyslaw Z Traczyk
    Abstract:

    The effect of 12 C-terminal hexapeptide analogs of substance P perfused into the Cerebral Ventricles on the trigemino-hypoglossal reflex caused by incisor pulp stimulation in rats was investigated. A substitution of the L-isomer by D at position 6, 7, or 8 of the substance P analogs used in this study caused the most pronounced inhibition of the trigemino-hypoglossal reflex. A correlation between the degree of inhibition of the reflex and concentration of the peptide used was observed.

Robert E London - One of the best experts on this subject based on the ideXlab platform.

  • differential clearance of nitroxide mri contrast agents from rat Cerebral Ventricles
    Brain Research Bulletin, 1995
    Co-Authors: Xiaoming Wan, Alex Funk, Robert E London
    Abstract:

    Abstract Seven stable nitroxides have been evaluated as contrast agents in MRI studies of the rat cerebroventrictdar system. Because the contrast enhancement is primarily confined to the Cerebral Ventricles, n1troxides can be used to examine the ventricular stricture. On the other hand, based on the absence of reducing agents in the rat CSF and on the fact that nitroxides can be reduced intracellularly, the relative reduction In contrast subsequent to an intraCerebral injection provides information on the relationship of chemical structure to transmembrane flux in vivo. Observed rate constants and rate constants due to reduction have been analyzed quantitatively by modeling the effects of flow with GdDTPA, which is not subject to reduction. Five-membered ring nitroxides, in general, were reduced at much slower rates than six-membered ring nitroxides. The presence of a positive charge in the structure can substantially slow down the transmembrane flux.

  • charge dependence of the distribution of contrast agents in rat Cerebral Ventricles
    Magnetic Resonance in Medicine, 1992
    Co-Authors: Xiaoming Wan, Robert E London
    Abstract:

    Previous studies of MRI contrast resulting from the intraCerebral administration of several contrast agents have suggested that the distribution of these agents may be dependent on the net charge. In order to further evaluate the significance of this parameter, the distribution of both aquo and CDTA-chelated lanthanide and transition metal ions in the Cerebral Ventricles of rats has been evaluated based on their enhancement of MRI contrast. The agents were injected directly into the lateral Ventricles of Sprague-Dawley rats. Each of five different positively charged paramagnetic metal ions tested selectively enhanced the inner cellular layers of ventricular luminal wall of the rat brain, while such enhancement was absent using the corresponding negatively charged metal-CDTA complexes. The abundance of negatively charged residues on the cell surface of the inner luminal layers is suggested to be the source of the observed charge affinity. Differences in the distribution of Mn2+ ions administered intraCerebrally compared with intraperitoneal (ip) injection suggest that while the first treatment may result primarily in uncomplexed aquo ions which then interact with the luminal surface, manganese ions administered ip behave more like chelated ions and are most probably complexed to transferrin.

Maria Zubrzycka - One of the best experts on this subject based on the ideXlab platform.

  • Effect of tooth pulp and periaqueductal central gray electrical stimulation on β-endorphin release into the fluid perfusing the Cerebral Ventricles in rats
    Brain Research, 2011
    Co-Authors: Maria Zubrzycka, Anna Janecka
    Abstract:

    Abstract Our previous studies demonstrated that tooth pulp stimulation increases the pain threshold, whereas stimulation of the periaqueductal central gray (PAG) has the opposite effect. The aim of this study was to investigate the effect exerted by electrical stimulation of the nociceptive afferent terminals in the tooth pulp and analgesic electrical stimulation of the PAG on the release of immunoreactive β-endorphin (β-EP-IR) into the cerebrospinal fluid (CSF) and artificial cerebrospinal fluid (aCSF) perfusing the Cerebral Ventricles in rat, and to establish whether during such stimulation the μ-opioid receptor (MOR) was activated. The tongue jerk reflex was induced by dental pulp stimulation in rats under chloralose anesthesia. CSF was collected from the cerebello-medullary cistern, and then 30-minute perfusions of the lateral Ventricles with aCSF were conducted with collection of perfusate portions from the cerebello-medullary cistern at rest (control), during electrical tooth pulp stimulation evoking the nociceptive tongue jerk reflex and during inhibition of that reflex with simultaneous stimulation of tooth pulp and the PAG. In the second series of experiments, a MOR-selective antagonist, β-funaltrexamine (β-FNA) was perfused through the Cerebral Ventricles 10 min before tooth pulp stimulation. β-EP-IR was determined in the collected CSF and aCSF perfusates by radioimmunoassay (RIA). Stimulation of tooth pulp with electrical impulses resulted in a significant increase of β-EP-IR. On the other hand, simultaneous tooth pulp and PAG stimulation inhibited β-EP-IR release into the fluid perfusing the Cerebral Ventricles. β-FNA blocked evoked tongue jerks (ETJ) induced by PAG stimulation, but no enhancing effect of β-FNA on β-EP-IR release into the perfusate was observed. The obtained results indicate that stimulation of the tooth pulp increases β-EP release significantly, whereas PAG stimulation significantly inhibits β-EP-IR release into the CSF, and that these effects are mediated by MOR. The results of the experiments allow to conclude that endogenous β-EP, released as a result of electrical tooth pulp stimulation in orofacial pain, diffuses through the cerebroventricular ependyma into the CSF and exerts a modulatory effect, mediated by MOR, alterating the properties of neurons in the trigeminal sensory nuclei, interneurons, and motoneurons of the hypoglossal nerve.

  • Substance P content in the cerebrospinal fluid and fluid perfusing Cerebral Ventricles during elicitation and inhibition of trigemino-hypoglossal reflex in rats
    Brain Research, 2002
    Co-Authors: Maria Zubrzycka, Anna Janecka
    Abstract:

    The aim of this study was to establish whether tooth pulp and periaqueductal central gray (PAG) stimulation affects the release of substance P (SP) into the fluid perfusing the Cerebral Ventricles in rats. The content of substance P in the cerebrospinal fluid and fluid perfusing Cerebral Ventricles was determined during incisor pulp stimulation with electrical impulses inducing nociceptive trigemino-hypoglossal reflex and then during inhibition of the reflex by stimulation of PAG. Perfusion of the Cerebral Ventricles was carried out using artificial cerebrospinal fluid (aCSF). SP-like immunoreactivity (SP-LI) was determined in the samples by radioimmunoassay. Samples were collected in four groups: first group-cerebrospinal fluid (CSF); second group-aCSF perfusates without stimulation; third group-aCSF perfusates during incisor pulp stimulation; fourth group-aCSF perfusates during incisor pulp stimulation and simultaneous inhibition of trigemino-hypoglossal reflex by PAG stimulation. It was shown that incisor pulp stimulation led to the increased release of SP-LI into the fluid perfusing Cerebral Ventricles. Stimulation of PAG reduced the release of SP-LI into the cerebro-ventricular system to the values obtained before the tooth pulp stimulation. The results indicate that PAG significantly inhibits the release of SP-LI into the rat Cerebral ventricular system and may be involved in the inhibition of trigemino-hypoglossal reflex.

  • comparison of antagonistic properties of substance p analogs spantide i ii and iii on evoked tongue jerks in rats
    Endocrine Regulations, 2000
    Co-Authors: Maria Zubrzycka, Anna Janecka, Wladyslaw Z Traczyk
    Abstract:

    OBJECTIVE: To study and evaluate the effects of perfusion through Cerebral Ventricles with substance P (SP) and its analogs: spantide I, II and III on evoked tongue jerks (ETJ) in male rats. METHODS: During the perfusion, stimulation of the tooth pulp caused retractive movements of the stretched tongue, the amplitudes of which were recorded. The mean amplitudes of evoked tongue jerks (ETJ) recorded during each 10 min. period of perfusion with McIlwain-Rodnight's solution and solutions containing peptides were compared. RESULTS: Perfusion of Cerebral Ventricles with SP caused a significant increase in the mean amplitude of evoked tongue jerks. Spantide I caused a complete respiratory arrest in all of the examined animals, so its effect on the trigemino-hypoglossal reflex could not have been tested. Spantide II, in the first two minutes, induced a transient significant decrease in ETJ amplitude, followed by an increase in ETJ in the next 8 min. SP perfused after spantide II caused a further significant increase in ETJ, as compared with control. Perfusion of Cerebral Ventricles with spantide III caused a significant, dose-dependent decrease in ETJ. SP perfused after spantide III caused a smaller increase in ETJ than it was observed without spantide III. CONCLUSION: Spantide III was found to be a strong antagonist of SP in trigemino-hypoglossal reflex.

  • inhibition of tongue reflex in rats by tooth pulp stimulation during Cerebral ventricle perfusion with 6 11 substance p analogs
    Brain Research, 1997
    Co-Authors: Maria Zubrzycka, Anna Janecka, Wiktor Koziolkiewicz, Wladyslaw Z Traczyk
    Abstract:

    The effect of 12 C-terminal hexapeptide analogs of substance P perfused into the Cerebral Ventricles on the trigemino-hypoglossal reflex caused by incisor pulp stimulation in rats was investigated. A substitution of the L-isomer by D at position 6, 7, or 8 of the substance P analogs used in this study caused the most pronounced inhibition of the trigemino-hypoglossal reflex. A correlation between the degree of inhibition of the reflex and concentration of the peptide used was observed.

Govind T Vatassery - One of the best experts on this subject based on the ideXlab platform.

  • brains of apolipoprotein e deficient mice fed vitamin e deficient diets show alteration in handling alpha tocopherol injected into the Cerebral Ventricles
    Journal of the Neurological Sciences, 2009
    Co-Authors: Govind T Vatassery, Ed W Smith, Hung T Quach
    Abstract:

    Abnormal function of apolipoprotein E (apoE) has been implicated in the incidence of some neurological disorders including dementia. Our recent experiments have shown that apoE deficiency alters the dynamics of alpha tocopherol (vitamin E) handling by brain. In the current investigation, we examined the uptake and retention of tritium-labeled alpha tocopherol that was injected into the lateral Cerebral Ventricles of apoE-deficient and wild type mice that were fed vitamin E-deficient diet. Eighteen weeks-old, male mice were fed vitamin E-deficient diets for 28 weeks. Labeled cholesterol was injected with the radioactive tocopherol and the cholesterol counts were used as internal standard. After an equilibration time of 48 h, radioactive alpha tocopherol levels in most brain regions were higher in apoE deficient animals when compared with the wild type. Along with our other data, this suggests that the clearance of vitamin E is slower in apoE-deficient brains. Nearly all of the injected alpha tocopherol was unchanged in the brains of both apoE-deficient and wild type animals (even with the additional dietary stress of vitamin E deficiency) suggesting low turnover rate of tocopherol in brain. The data strongly suggest that apoE is a key protein involved with the transport and/or retention of alpha tocopherol in brain.

  • apolipoprotein e deficiency leads to altered brain uptake of alpha tocopherol injected into lateral Cerebral Ventricles
    Biochimica et Biophysica Acta, 2007
    Co-Authors: Govind T Vatassery, Hung T Quach, Ed W Smith, Karen Santacruz, Siddhartha Roy
    Abstract:

    The incorporation of radioactive alpha tocopherol by various brain regions of wild type and apolipoprotein E (apoE)-deficient mice was investigated. Labeled tocopherol was injected into the lateral Cerebral Ventricles of 11 weeks old, male mice. Radioactive cholesterol injected simultaneously was used as an internal standard to account for experimental variability. Most areas of the brain of apoE-deficient mice took up less of alpha tocopherol per mg of protein than wild type animals. However, specific activity of alpha tocopherol was higher in cerebellum, pons, hypothalamus, midbrain and Cerebral cortex in apoE-deficient brains than the wild type. This could be due to (a) the lower levels of alpha tocopherol in apoE-deficient brain and (b) reductions in the clearance and transport of tocopherol (possibly mediated by apoE). Tocopherol uptake by hippocampus was unusual since it was lower in apoE deficiency whether the data were expressed as specific activity or per mg of protein. Nearly all of the injected alpha tocopherol remained unchanged in the brains of both apoE-deficient and wild type animals suggesting low turnover. Overall, the current data reinforce the hypothesis that apoE is a key protein involved with the transport and/or retention of alpha tocopherol in brain.

Lynne E Bilston - One of the best experts on this subject based on the ideXlab platform.

  • Effect of endoscopic third ventriculostomy on cerebrospinal fluid pressure in the Cerebral Ventricles
    'Elsevier BV', 2016
    Co-Authors: Farnoush A, Lynne E Bilston, Tan K, Juge L, Cheng S
    Abstract:

    © 2015 Elsevier Ltd. All rights reserved. We aimed to show how endoscopic third ventriculostomy (ETV) treatment may affect cerebrospinal fluid (CSF) flow dynamics in hydrocephalus, with and without aqueductal stenosis. Hydrocephalus is a neurological disorder which is characterized by enlarged brain Ventricles. The periodic motion of CSF flow as a function of the cardiac cycle was prescribed as the inlet boundary condition at the foramen of Monro, and ETV was modeled as a 5 mm diameter hole in the anterior wall of the third ventricle. The results show that ETV reduces the pressure in the Ventricles by nine-fold in the model with aqueductal stenosis, and three-fold in the model without aqueductal stenosis. More importantly, ETV changes the temporal characteristics of the CSF pressure waveform in the model without aqueductal stenosis, such that there is higher pressure in the ventricle during diastole. This study suggests that changes in the temporal characteristics of the CSF pressure waveform in the Ventricles may be the reason why ETV treatment is not effective for hydrocephalus without aqueductal stenosis

  • Computational Model of the Cerebral Ventricles in Hydrocephalus
    Journal of biomechanical engineering, 2010
    Co-Authors: Shaokoon Cheng, Lynne E Bilston
    Abstract:

    Understanding the mechanisms of tissue injury in hydrocephalus is important to shed light on the pathophysiology of this neurostructural disorder. To date, most of the finite element models created to study hydrocephalus have been two-dimensional (2D). This may not be adequate as the geometry of the Cerebral Ventricles is unique. In this study, a three-dimensional (3D) finite element model of the Cerebral Ventricles during hydrocephalus is presented. Results from this model show that during hydrocephalus, the periventricular regions experience the highest stress, and stress magnitude is approximately 80 times higher than the Cerebral mantle. This suggests that functional deficits observed in hydrocephalic patients could therefore be more related to the damage to periventricular white matter. In addition, the stress field simulated in the tissues based on the 3D model was found to be approximately four times lower than on the 2D model.

  • the effects of the interthalamic adhesion position on cerebrospinal fluid dynamics in the Cerebral Ventricles
    Journal of Biomechanics, 2010
    Co-Authors: Shaokoon Cheng, Lynne E Bilston
    Abstract:

    The interthalamic adhesion is a unique feature of the third ventricle in the brain. It differs in shape and size and its location varies between individuals. In this study, computational fluid dynamics was performed on 4 three-dimensional models of the Cerebral ventricular system with the interthalamic adhesion modeled in different locations in the third ventricle. Cerebrospinal fluid (CSF) was modeled as incompressible Newtonian fluid and flow was assumed laminar. The periodic motion of CSF flow as a function of the cardiac cycle starting from diastole was prescribed as the inlet boundary condition at the foramen of Monroe. Results from this study show how the location of the interthalamic adhesion influences the pattern of pressure distribution in the Cerebral Ventricles. In addition, the highest CSF pressure in the third ventricle can vary by ∼50% depending on the location of the interthalamic adhesion. We suggest that the interthalamic adhesion may have functional implications on the development of hydrocephalus and it is important to model this anatomical feature in future studies.