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Hannah C. Kinney - One of the best experts on this subject based on the ideXlab platform.
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Decreased kainate receptor binding in the Arcuate Nucleus of the sudden infant death syndrome.
Journal of neuropathology and experimental neurology, 1997Co-Authors: Ashok Panigrahy, James J. Filiano, Lynn A Sleeper, Frederick Mandell, W F White, Marie Valdes-dapena, Henry F. Krous, Luciana A. Rava, Hannah C. KinneyAbstract:The human Arcuate Nucleus is postulated to be homologous to ventral medullary surface cells in animals that participate in ventilatory and blood pressure responses to hypercarbia and asphyxia. Recently, we reported a significant decrease in muscarinic cholinergic receptor binding in the Arcuate Nucleus in victims of the sudden infant death syndrome compared with control patients that died of acute causes. To test the specificity of the deficit to muscarinic cholinergic binding, we examined kainate binding in the Arcuate Nucleus in the same database. We assessed 3H-kainate binding to kainate receptors with tissue receptor autoradiography in 17 brainstem nuclei. Analysis of covariance was used to examine differences in binding by diagnosis, adjusted for postconceptional age (the covariate). Cases were classified as SIDS, 47; acute control, 15; and chronic group with oxygenation disorder, 17. (Acute controls are infants who died suddenly and unexpectedly and in whom a complete autopsy established a cause of death). The Arcuate Nucleus was the only region in which there was a significant difference in the age-adjusted mean kainate binding between the SIDS group (37+/-2 fmol/mg tissue) and both the acute controls (77+/-4 fmol/mg tissue) (p < 0.0001) and the chronic group (69+/-4 fmol/mg tissue) (p < 0.0001). There was a positive correlation between the density of muscarinic cholinergic and kainate binding in the SIDS cases only (R = 0.460; p = 0.003). The neurotransmitter deficit in the Arcuate Nucleus in SIDS victims involves more than one receptor type relevant to carbon dioxide and blood pressure responses at the ventral medullary surface.
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decreased muscarinic receptor binding in the Arcuate Nucleus in sudden infant death syndrome
Science, 1995Co-Authors: Hannah C. Kinney, James J. Filiano, Lynn A Sleeper, Frederick Mandell, M Valdesdapena, W F WhiteAbstract:Muscarinic cholinergic activity in the human Arcuate Nucleus at the ventral medullary surface is postulated to be involved in cardiopulmonary control. A significant decrease in [3H]quinuclidinyl benzilate binding to muscarinic receptors in the Arcuate Nucleus is now shown to occur in sudden infant death syndrome (SIDS) infants, compared to infants dying acutely of known causes. In infants with chronic oxygenation abnormalities, binding is low in other nuclei, as well as in the Arcuate Nucleus. The binding deficit in the Arcuate Nucleus of SIDS infants might contribute to a failure of responses to cardiopulmonary challenges during sleep.
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Arcuate Nucleus hypoplasia in the sudden infant death syndrome.
Journal of neuropathology and experimental neurology, 1992Co-Authors: James J. Filiano, Hannah C. KinneyAbstract:Abnormalities in central respiratory control during sleep, arousal and/or cardiac activity have been reported in some infants who subsequently die of the sudden infant death syndrome (SIDS). We postulate that these abnormalities may result from dysfunction of the ventral and ventrolateral medulla, which, based on animal data, is an integrative site for chemosensitivity, ventilation, autonomic function, and arousal. The Arcuate Nucleus along the ventral surface of the human medulla has been proposed to facilitate chemosensitivity to carbon dioxide and/or hydrogen ion. In this study, we surveyed serially or extensively sectioned medullae of 41 SIDS and 27 controls, and identified two SIDS victims with isolated hypoplasia of the Arcuate Nucleus. Three-dimensional reconstructions and volume measurements of each hemimedulla of one of these SIDS victims and three controls were performed from serial sections. The volume of the right Arcuate Nucleus of the SIDS case was 0.7 mm3, compared to a range of 3.4-26.3 mm3 (median 5 mm3) in three infant controls. On the basis of the anatomic connections of the human Arcuate Nucleus and of neurons in homologous positions in animals, we postulate that Arcuate hypoplasia may lead to death by dyssynergy between cerebellar coordination of ventilation and autonomic/chemosensory/arousal integration, especially during sleep, hypercarbia, and in a critical developmental period.
Naomi E Rance - One of the best experts on this subject based on the ideXlab platform.
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coexpression of dynorphin and neurokinin b immunoreactivity in the rat hypothalamus morphologic evidence of interrelated function within the Arcuate Nucleus
The Journal of Comparative Neurology, 2006Co-Authors: Michelle C Burke, Penny A Letts, Sally J Krajewski, Naomi E RanceAbstract:Considerable evidence suggests that dynorphin and neurokinin B (NKB) neurons in the hypothalamic Arcuate Nucleus participate in the sex-steroid regulation of reproduction. In the present study, we used dual-label immunofluorescence to explore the distribution of prodynorphin and proNKB immunoreactivity in the rat hypothalamus. Additionally, we investigated whether Arcuate prodynorphin-ir (immunoreactive) neurons expressed the neurokinin 3 receptor (NK3R) or nuclear estrogen receptor-alpha (ERalpha). We found that the majority of prodynorphin-ir neurons in the rat Arcuate Nucleus expressed proNKB, whereas nearly all (99%) of the proNKB neurons were immunoreactive for prodynorphin. The Arcuate Nucleus was the only site in the hypothalamus where neuronal somata coexpressing prodynorphin and proNKB-immunoreactivity were identified. A dense plexus of double-labeled prodynorphin/proNKB-ir fibers was found within the Arcuate Nucleus extending to the median eminence and throughout the periventricular zone of the hypothalamus. Prodynorphin/proNKB fibers were also identified in the paraventricular Nucleus, anterior hypothalamic area, medial preoptic area, median preoptic Nucleus, anteroventral periventricular Nucleus, and bed Nucleus of the stria terminalis in a distribution consistent with previously described Arcuate Nucleus projections. Interestingly, the majority of prodynorphin-ir neurons in the Arcuate Nucleus expressed NK3R, and nearly 100% of the prodynorphin-ir neurons contained nuclear ERalpha. Our results suggest that there is a close functional relationship between dynorphin and NKB peptides within the Arcuate Nucleus of the rat, which may include an autofeedback loop mediated through NK3R. The diverse hypothalamic projections of fibers expressing both prodynorphin and proNKB provide evidence that these neurons may participate in a variety of homeostatic and neuroendocrine processes.
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coexpression of dynorphin and neurokinin b immunoreactivity in the rat hypothalamus morphologic evidence of interrelated function within the Arcuate Nucleus
The Journal of Comparative Neurology, 2006Co-Authors: Michelle C Burke, Penny A Letts, Sally J Krajewski, Naomi E RanceAbstract:Considerable evidence suggests that dynorphin and neurokinin B (NKB) neurons in the hypothalamic Arcuate Nucleus participate in the sex-steroid regulation of reproduction. In the present study, we used dual-label immunofluorescence to explore the distribution of prodynorphin and proNKB immunoreactivity in the rat hypothalamus. Additionally, we investigated whether Arcuate prodynorphin-ir (immunoreactive) neurons expressed the neurokinin 3 receptor (NK3R) or nuclear estrogen receptor-α (ERα). We found that the majority of prodynorphin-ir neurons in the rat Arcuate Nucleus expressed proNKB, whereas nearly all (99%) of the proNKB neurons were immunoreactive for prodynorphin. The Arcuate Nucleus was the only site in the hypothalamus where neuronal somata coexpressing prodynorphin and proNKB-immunoreactivity were identified. A dense plexus of double-labeled prodynorphin/proNKB-ir fibers was found within the Arcuate Nucleus extending to the median eminence and throughout the periventricular zone of the hypothalamus. Prodynorphin/proNKB fibers were also identified in the paraventricular Nucleus, anterior hypothalamic area, medial preoptic area, median preoptic Nucleus, anteroventral periventricular Nucleus, and bed Nucleus of the stria terminalis in a distribution consistent with previously described Arcuate Nucleus projections. Interestingly, the majority of prodynorphin-ir neurons in the Arcuate Nucleus expressed NK3R, and nearly 100% of the prodynorphin-ir neurons contained nuclear ERα. Our results suggest that there is a close functional relationship between dynorphin and NKB peptides within the Arcuate Nucleus of the rat, which may include an autofeedback loop mediated through NK3R. The diverse hypothalamic projections of fibers expressing both prodynorphin and proNKB provide evidence that these neurons may participate in a variety of homeostatic and neuroendocrine processes. J. Comp. Neurol. 498:712–726, 2006. © 2006 Wiley-Liss, Inc.
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neurokinin b gene expression is increased in the Arcuate Nucleus of ovariectomized rats
Neuroendocrinology, 1994Co-Authors: Naomi E Rance, Tami R BruceAbstract:Hypertrophy and increased gene expression of tachykinin neurons occur in the infundibular (Arcuate) Nucleus of postmenopausal women. We have hypothesized that the alterations in tachykinin gene expres
James J. Filiano - One of the best experts on this subject based on the ideXlab platform.
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Decreased kainate receptor binding in the Arcuate Nucleus of the sudden infant death syndrome.
Journal of neuropathology and experimental neurology, 1997Co-Authors: Ashok Panigrahy, James J. Filiano, Lynn A Sleeper, Frederick Mandell, W F White, Marie Valdes-dapena, Henry F. Krous, Luciana A. Rava, Hannah C. KinneyAbstract:The human Arcuate Nucleus is postulated to be homologous to ventral medullary surface cells in animals that participate in ventilatory and blood pressure responses to hypercarbia and asphyxia. Recently, we reported a significant decrease in muscarinic cholinergic receptor binding in the Arcuate Nucleus in victims of the sudden infant death syndrome compared with control patients that died of acute causes. To test the specificity of the deficit to muscarinic cholinergic binding, we examined kainate binding in the Arcuate Nucleus in the same database. We assessed 3H-kainate binding to kainate receptors with tissue receptor autoradiography in 17 brainstem nuclei. Analysis of covariance was used to examine differences in binding by diagnosis, adjusted for postconceptional age (the covariate). Cases were classified as SIDS, 47; acute control, 15; and chronic group with oxygenation disorder, 17. (Acute controls are infants who died suddenly and unexpectedly and in whom a complete autopsy established a cause of death). The Arcuate Nucleus was the only region in which there was a significant difference in the age-adjusted mean kainate binding between the SIDS group (37+/-2 fmol/mg tissue) and both the acute controls (77+/-4 fmol/mg tissue) (p < 0.0001) and the chronic group (69+/-4 fmol/mg tissue) (p < 0.0001). There was a positive correlation between the density of muscarinic cholinergic and kainate binding in the SIDS cases only (R = 0.460; p = 0.003). The neurotransmitter deficit in the Arcuate Nucleus in SIDS victims involves more than one receptor type relevant to carbon dioxide and blood pressure responses at the ventral medullary surface.
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decreased muscarinic receptor binding in the Arcuate Nucleus in sudden infant death syndrome
Science, 1995Co-Authors: Hannah C. Kinney, James J. Filiano, Lynn A Sleeper, Frederick Mandell, M Valdesdapena, W F WhiteAbstract:Muscarinic cholinergic activity in the human Arcuate Nucleus at the ventral medullary surface is postulated to be involved in cardiopulmonary control. A significant decrease in [3H]quinuclidinyl benzilate binding to muscarinic receptors in the Arcuate Nucleus is now shown to occur in sudden infant death syndrome (SIDS) infants, compared to infants dying acutely of known causes. In infants with chronic oxygenation abnormalities, binding is low in other nuclei, as well as in the Arcuate Nucleus. The binding deficit in the Arcuate Nucleus of SIDS infants might contribute to a failure of responses to cardiopulmonary challenges during sleep.
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Arcuate Nucleus hypoplasia in the sudden infant death syndrome.
Journal of neuropathology and experimental neurology, 1992Co-Authors: James J. Filiano, Hannah C. KinneyAbstract:Abnormalities in central respiratory control during sleep, arousal and/or cardiac activity have been reported in some infants who subsequently die of the sudden infant death syndrome (SIDS). We postulate that these abnormalities may result from dysfunction of the ventral and ventrolateral medulla, which, based on animal data, is an integrative site for chemosensitivity, ventilation, autonomic function, and arousal. The Arcuate Nucleus along the ventral surface of the human medulla has been proposed to facilitate chemosensitivity to carbon dioxide and/or hydrogen ion. In this study, we surveyed serially or extensively sectioned medullae of 41 SIDS and 27 controls, and identified two SIDS victims with isolated hypoplasia of the Arcuate Nucleus. Three-dimensional reconstructions and volume measurements of each hemimedulla of one of these SIDS victims and three controls were performed from serial sections. The volume of the right Arcuate Nucleus of the SIDS case was 0.7 mm3, compared to a range of 3.4-26.3 mm3 (median 5 mm3) in three infant controls. On the basis of the anatomic connections of the human Arcuate Nucleus and of neurons in homologous positions in animals, we postulate that Arcuate hypoplasia may lead to death by dyssynergy between cerebellar coordination of ventilation and autonomic/chemosensory/arousal integration, especially during sleep, hypercarbia, and in a critical developmental period.
R. Magoul - One of the best experts on this subject based on the ideXlab platform.
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Tachykinergic synaptic inputs to neurons of the medial preoptic region which project to the rat Arcuate Nucleus.
Neuroscience letters, 1994Co-Authors: R. Magoul, P Dubourg, O Kah, G TramuAbstract:Anatomical relationships between tachykinin-containing terminals and neurons of the medial preoptic area that innervate the Arcuate Nucleus were studied using silver staining of the retrograde tracer wheat germ agglutinin-apoperoxidase-gold (WGA-ApoHRP-gold) complex injected in the Arcuate Nucleus and pre-embedding immunocytochemistry for neurokinin A (NKA). At the histological level, retrogradely labeled cells not stained for NKA were seen to be surrounded by numerous NKA-immunopositive punctate profiles, in particular in the dorsal part of the medial preoptic area. At the ultrastructural level, retrogradely labeled cell bodies and dendritic profiles displayed highly electron-dense silver particle accumulations over the cytoplasm. The were seen in synaptic contact with one or several NKA-immunoreactive axon terminals containing small clear vesicles and dense-cored vesicles. Such synapses were either symmetrical or asymmetrical. The occurrence of synaptic contacts between tachykinin terminals and cells innervating the Arcuate Nucleus in the medial preoptic region provides a morphological support for a tachykinergic regulation of preoptic afferences to the Arcuate Nucleus. These results suggest that tachykinins are implicated in the indirect control of neuronal activity in the Arcuate Nucleus notably via the preoptic area. Consequently, tachykinins are potentially able to regulate indirectly numerous neuroendocrine events involving the tuberoinfundibular system.
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Direct and indirect enkephalinergic synaptic inputs to the rat Arcuate Nucleus studied by combination of retrograde tracing and immunocytochemistry.
Neuroscience, 1993Co-Authors: R. Magoul, Pierrette Dubourg, W. Benjelloun, Gérard TramuAbstract:The origin of both direct and indirect enkephalinergic innervation potentially able to influence neurons of the rat Arcuate Nucleus has been investigated by combining enkephalin immunocytochemistry and retrograde axonal transport of a wheatgerm agglutinin-Apo horseradish peroxidase-gold complex. Twenty four hours after tissue injections of small volumes (20 nl) of the tracer into the Arcuate Nucleus, rats were treated with colchicine and killed. In order to localize the enkephalinergic cells which directly innervate the Arcuate Nucleus, Vibratome sections were first silver-stained for detection of the wheatgerm agglutinin-Apohorseradish peroxidase-gold complex and then processed for enkephalin immunohistochemistry. To study the indirect enkephalinergic input to the Arcuate Nucleus, an electron microscope detection of immunoreactive synapses was carried out in areas rich in retrogradely labeled perikarya. Perikarya both immunoreactive and retrogradely labeled were observed ipsilaterally to the injection site in telencephalic structures such as the bed Nucleus of the stria terminalis, medial preoptic and adjacent periventricular areas. Hypothalamic ipsilateral doubly labeled cells were localized principally in the dorsomedial Nucleus and rostral Arcuate Nucleus. The major direct inputs arising from brainstem structures concerns the dorsal and ventral parabrachial nuclei. Moreover, at the ultrastructural level, numerous enkephalinergic terminals were demonstrated to synapse with retrogradely labeled perikarya and dendrites localized in the medial preoptic area, the hypothalamic paraventricular Nucleus and the parabrachial nuclei providing evidence for an important enkephalinergic input on neurons projecting to the Arcuate Nucleus. Taken together, our light and electron microscope studies strongly suggest that the Arcuate Nucleus is the target of an enkephalinergic control originating from several regions and acting either directly or indirectly on neurons projecting to the Arcuate Nucleus.
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Tachykinergic afferents to the rat Arcuate Nucleus. A combined immunohistochemical and retrograde tracing study.
Peptides, 1993Co-Authors: R. Magoul, Brigitte Onteniente, Wail Benjelloun, Gérard TramuAbstract:The location of the cells giving rise to the tachykinergic innervation of the rat Arcuate Nucleus was studied by combining immunohistochemistry and retrograde axonal transport of a protein-gold complex (WGA-ApoHRP-gold). Small volumes (20 nl) of this marker were injected into the Arcuate Nucleus of the rat. Twenty-four to 30 h later, rats were injected with colchicine. After 24-h survival time, the paraformaldehyde-fixed brains were investigated for silver intensification of the gold particles and for tachykinin immunohistochemistry. Doubly immuno-silver-labeled cells were observed mainly in brainstem structures such as raphe nuclei, central gray pontine, and laterodorsal tegmental Nucleus. Intranuclear and intrahypothalamic (ventromedial, dorsomedial, premamillary, and supramamillary) cell bodies were also doubly labeled, principally ipsilateral to the injection site. Minor afferent projections arise from the medial preoptic area. This anatomohistochemical study demonstrates that the Arcuate Nucleus receives intra- and extrahypothalamic tachykinergic inputs and shows that infundibular neurons undergo convergent tachykinergic influences.
Gérard Tramu - One of the best experts on this subject based on the ideXlab platform.
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Direct and indirect enkephalinergic synaptic inputs to the rat Arcuate Nucleus studied by combination of retrograde tracing and immunocytochemistry.
Neuroscience, 1993Co-Authors: R. Magoul, Pierrette Dubourg, W. Benjelloun, Gérard TramuAbstract:The origin of both direct and indirect enkephalinergic innervation potentially able to influence neurons of the rat Arcuate Nucleus has been investigated by combining enkephalin immunocytochemistry and retrograde axonal transport of a wheatgerm agglutinin-Apo horseradish peroxidase-gold complex. Twenty four hours after tissue injections of small volumes (20 nl) of the tracer into the Arcuate Nucleus, rats were treated with colchicine and killed. In order to localize the enkephalinergic cells which directly innervate the Arcuate Nucleus, Vibratome sections were first silver-stained for detection of the wheatgerm agglutinin-Apohorseradish peroxidase-gold complex and then processed for enkephalin immunohistochemistry. To study the indirect enkephalinergic input to the Arcuate Nucleus, an electron microscope detection of immunoreactive synapses was carried out in areas rich in retrogradely labeled perikarya. Perikarya both immunoreactive and retrogradely labeled were observed ipsilaterally to the injection site in telencephalic structures such as the bed Nucleus of the stria terminalis, medial preoptic and adjacent periventricular areas. Hypothalamic ipsilateral doubly labeled cells were localized principally in the dorsomedial Nucleus and rostral Arcuate Nucleus. The major direct inputs arising from brainstem structures concerns the dorsal and ventral parabrachial nuclei. Moreover, at the ultrastructural level, numerous enkephalinergic terminals were demonstrated to synapse with retrogradely labeled perikarya and dendrites localized in the medial preoptic area, the hypothalamic paraventricular Nucleus and the parabrachial nuclei providing evidence for an important enkephalinergic input on neurons projecting to the Arcuate Nucleus. Taken together, our light and electron microscope studies strongly suggest that the Arcuate Nucleus is the target of an enkephalinergic control originating from several regions and acting either directly or indirectly on neurons projecting to the Arcuate Nucleus.
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Tachykinergic afferents to the rat Arcuate Nucleus. A combined immunohistochemical and retrograde tracing study.
Peptides, 1993Co-Authors: R. Magoul, Brigitte Onteniente, Wail Benjelloun, Gérard TramuAbstract:The location of the cells giving rise to the tachykinergic innervation of the rat Arcuate Nucleus was studied by combining immunohistochemistry and retrograde axonal transport of a protein-gold complex (WGA-ApoHRP-gold). Small volumes (20 nl) of this marker were injected into the Arcuate Nucleus of the rat. Twenty-four to 30 h later, rats were injected with colchicine. After 24-h survival time, the paraformaldehyde-fixed brains were investigated for silver intensification of the gold particles and for tachykinin immunohistochemistry. Doubly immuno-silver-labeled cells were observed mainly in brainstem structures such as raphe nuclei, central gray pontine, and laterodorsal tegmental Nucleus. Intranuclear and intrahypothalamic (ventromedial, dorsomedial, premamillary, and supramamillary) cell bodies were also doubly labeled, principally ipsilateral to the injection site. Minor afferent projections arise from the medial preoptic area. This anatomohistochemical study demonstrates that the Arcuate Nucleus receives intra- and extrahypothalamic tachykinergic inputs and shows that infundibular neurons undergo convergent tachykinergic influences.