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Ramón Anadón - One of the best experts on this subject based on the ideXlab platform.
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Experimental study of the connections of the preglomerular nuclei and corpus mamillare in the rainbow trout, Oncorhynchus mykiss
Brain Research Bulletin, 2005Co-Authors: Monica Folgueira, Ramón Anadón, Julian YanezAbstract:The preglomerular complex of trout consists of the anterior (aPGN) and medial (mPGN) preglomerular nuclei and the corpus mamillare (CM). In order to improve knowledge on this complex, we applied a lipophilic neuronal tracer (DiI) to the three nuclei. These nuclei received afferents from the medial part of the dorsal telencephalic area (Dm), the ventral part of the ventral telencephalic area (Vv), the preoptic Nucleus, the periventricular layer of the rostral optic tectum and the central posterior thalamic Nucleus. The aPGN also received numerous toral projections and, sent efferents to the anterior Tuberal Nucleus. In addition, both the aPGN and the mPGN nuclei gave rise to efferents to the dorsal region of the dorsal telencephalic area (Dd), whereas the medial preglomerular Nucleus and the CM sent fibers to the torus lateralis and the diffuse Nucleus, as confirmed by reciprocal labeling. A small mPGN/CM subgroup projected to the optic tectum. These results suggest close functional inter-relationship between the trout preglomerular complex and two telencephalic regions (Dm and Vv). In addition, all nuclei of the complex receive preoptic, tectal and dorsal thalamic afferents, whereas the aPGN and mPGN are related with acoustic-lateral ascending pathways, and the mPGN and CM with the central region of the dorsal telencephalic area and visceral/gustatory pathways.
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experimental study of the connections of the telencephalon in the rainbow trout oncorhynchus mykiss ii dorsal area and preoptic region
The Journal of Comparative Neurology, 2004Co-Authors: Monica Folgueira, Ramón Anadón, Julian YanezAbstract:In this study and the accompanying article (Folgueira et al., 2004a), the fluorescent carbocyanine dye 1,1-dioctadecyl 3,3,3,3-tetramethylindocarbocyanine perchlorate (DiI) was used in fixed tissue to comprehensively analyze the connections of the different regions of the telencephalic lobes and the preoptic region of the rainbow trout. Here, we analyze the connections of the dorsal area (D; pallium) of the telencephalon, and the preoptic region, as well as the telencephalic connections of several structures in the diencephalon and brainstem of juvenile trout. The dorsal plus dorsolateral pallial zone of D (DdDl-d) receives afferents from contralateral DdDl-d, the ventral area of the telencephalon, preoptic Nucleus, suprachiasmatic Nucleus, medial thalamus, preglomerular complex, anterior and lateral Tuberal nuclei, posterior Tuberal Nucleus, posterior hypothalamic lobe, superior raphe Nucleus, and the rhombencephalic central gray and reticular formation, and projects to the central zone of D (Dc), medial thalamus, and some caudomedial hypothalamic regions. The medial zone of D (Dm) maintains reciprocal connections with the preglomerular complex and also receives afferents from the preoptic Nucleus, suprachiasmatic Nucleus, anterior Tuberal Nucleus, preglomerular tertiary gustatory Nucleus, posterior tubercle, superior raphe Nucleus, locus coeruleus, and the rhombencephalic central gray, and reticular formation. Dc receives fibers mainly from DdDl-d, preoptic Nucleus, preglomerular complex, and torus semicircularis and projects to several extratelencephalic centers, including the paracommissural Nucleus, optic tectum, torus semicircularis, thalamus, preglomerular complex, posterior tubercle nuclei, and inferior hypothalamic lobes. The posterior zone of D (Dp) is mainly connected with the olfactory bulbs, the ventral and supracommissural nuclei of the ventral area (subpallium), the preoptic Nucleus, and the preglomerular complex and projects to wide hypothalamic and posterior tubercular regions. The preoptic Nucleus projects to the olfactory bulb, to most regions of the telencephalic lobes, and to several diencephalic and brainstem structures. These results reveal complex and specialized connectional patterns in the rainbow trout dorsal telencephalon and preoptic region. Most of these connections have not been described previously in salmonids. These connections indicate that the salmonid telencephalon is involved in multisensorial processing and modulation of brain activity. J. Comp. Neurol. 480:204–233, 2004. © 2004 Wiley-Liss, Inc. Indexing terms: olfactory bulb; pallium; thalamus; torus semicircularis; cerebellum; teleost
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Distribution of thyrotropin-releasing hormone (TRH) immunoreactivity in the brain of the zebrafish (Danio rerio).
The Journal of comparative neurology, 2002Co-Authors: María Luz Díaz, María Jesús Manso, Manuela Becerra, Ramón AnadónAbstract:The distribution of thyrotropin-releasing hormone (TRH) in the brain of the adult zebrafish was studied with immunohistochemical techniques. In the telencephalon, abundant TRH-immunoreactive (TRHir) neurons were observed in the central, ventral, and supra- and postcommissural regions of the ventral telencephalic area. In the diencephalon, TRHir neurons were observed in the anterior parvocellular preoptic Nucleus, the suprachiasmatic Nucleus, the lateral hypothalamic Nucleus, the rostral parts of the anterior Tuberal Nucleus and torus lateralis, and the posterior Tuberal Nucleus. Some TRHir neurons were also observed in the central posterior thalamic Nucleus and in the habenula. The mesencephalon contained TRHir cells in the rostrodorsal tegmentum, the Edinger-Westphal Nucleus, the torus semicircularis, and the Nucleus of the lateral lemniscus. Further TRHir neurons were observed in the interpeduncular Nucleus. In the rhombencephalon, TRHir cells were observed in the Nucleus isthmi and the locus coeruleus, rostrally, and in the vagal lobe and vagal motor Nucleus, caudally. In the forebrain, TRHir fibers were abundant in several regions, including the medial and caudodorsal parts of the dorsal telencephalic area, the ventral and commissural parts of the ventral telencephalic area, the preoptic area, the posterior tubercle, the anterior Tuberal Nucleus, and the posterior hypothalamic lobe. The dorsal thalamus exhibited moderate TRHir innervation. In the mesencephalon, the optic tectum received a rich TRHir innervation between the periventricular gray zone and the stratum griseum centrale. A conspicuous TRHir longitudinal tract traversed the tegmentum and extended to the rhombencephalon. The medial and lateral mesencephalic reticular areas and the interpeduncular Nucleus were richly innervated by TRHir fibers. In the rhombencephalon, the secondary gustatory Nucleus received abundant TRHir fibers. TRHir fibers moderately innervated the ventrolateral and ventromedial reticular area and richly innervated the vagal lobe and Cajal's commissural Nucleus. Some TRHir fibers coursed in the lateral funiculus of the spinal cord. Some TRHir amacrine cells were observed in the retina. The wide distribution of TRHir neurons and fibers observed in the zebrafish brain suggests that TRH plays different roles. These results in the adult zebrafish reveal a number of differences with respect to the TRHir systems reported in other adult teleosts but were similar to those found during late developmental stages of trout (Diaz et al., 2001).
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distribution of tyrosine hydroxylase th and dopamine β hydroxylase dbh immunoreactivity in the central nervous system of two chondrostean fishes acipenser baeri and huso huso
The Journal of Comparative Neurology, 2002Co-Authors: Fátima Adrio, Ramón Anadón, Isabel RodriguezmoldesAbstract:To obtain a better understanding of the evolution of the brain catecholaminergic systems of fishes, we have examined the distribution of catecholamine-synthesizing enzymes in two species of sturgeon (Acipenser baeri and Huso huso) using antibodies against tyrosine hydroxylase (TH) and dopamine-β -hydroxylase (DBH; only analyzed in Acipenser). Both sturgeons showed TH-immunoreactive (THir) neurons widely distributed in most regions of the brain, the highest number of THir cells being located in the forebrain (olfactory bulb, preoptic area, and posterior tuberculum). THir cells were also seen in other forebrain areas (retrobulbar area, dorsal and ventral telencephalic areas, hypothalamus, ventral thalamus, pretectal area) and in the brainstem (locus coeruleus, viscerosensory area, caudal reticular formation, and area postrema). Immunoreactive fibers and varicosities showed a wide distribution, being particularly abundant in the diencephalon and mesencephalon. DBH-immunoreactive (DBHir) cells were observed in the anterior Tuberal Nucleus, where these cells were TH-negative, and in the locus coeruleus and the caudal rhombencephalon (vagal reticular formation), where the DBHir cells were also THir. DBHir fibers were scarce in the telencephalon and very abundant in the diencephalon, mesencephalon, and rhombencephalon. The comparative analysis of the catecholaminergic systems of chondrosteans and those observed in other groups of fishes and tetrapods indicate a similar organization of many nuclei, as well as characteristics that are probably primitive, such as the presence of a large number of forebrain catecholaminergic groups. J. Comp. Neurol. 448:280–297, 2002. © 2002 Wiley-Liss, Inc.
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Distribution of tyrosine hydroxylase (TH) and dopamine β‐hydroxylase (DBH) immunoreactivity in the central nervous system of two chondrostean fishes (Acipenser baeri and Huso huso)
The Journal of comparative neurology, 2002Co-Authors: Fátima Adrio, Ramón Anadón, Isabel Rodríguez-moldesAbstract:To obtain a better understanding of the evolution of the brain catecholaminergic systems of fishes, we have examined the distribution of catecholamine-synthesizing enzymes in two species of sturgeon (Acipenser baeri and Huso huso) using antibodies against tyrosine hydroxylase (TH) and dopamine-β -hydroxylase (DBH; only analyzed in Acipenser). Both sturgeons showed TH-immunoreactive (THir) neurons widely distributed in most regions of the brain, the highest number of THir cells being located in the forebrain (olfactory bulb, preoptic area, and posterior tuberculum). THir cells were also seen in other forebrain areas (retrobulbar area, dorsal and ventral telencephalic areas, hypothalamus, ventral thalamus, pretectal area) and in the brainstem (locus coeruleus, viscerosensory area, caudal reticular formation, and area postrema). Immunoreactive fibers and varicosities showed a wide distribution, being particularly abundant in the diencephalon and mesencephalon. DBH-immunoreactive (DBHir) cells were observed in the anterior Tuberal Nucleus, where these cells were TH-negative, and in the locus coeruleus and the caudal rhombencephalon (vagal reticular formation), where the DBHir cells were also THir. DBHir fibers were scarce in the telencephalon and very abundant in the diencephalon, mesencephalon, and rhombencephalon. The comparative analysis of the catecholaminergic systems of chondrosteans and those observed in other groups of fishes and tetrapods indicate a similar organization of many nuclei, as well as characteristics that are probably primitive, such as the presence of a large number of forebrain catecholaminergic groups. J. Comp. Neurol. 448:280–297, 2002. © 2002 Wiley-Liss, Inc.
Vance L Trudeau - One of the best experts on this subject based on the ideXlab platform.
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GABAergic Neurons and Their Modulatory Effects on GnRH3 in Zebrafish
Endocrinology, 2017Co-Authors: Yanlong Song, Ji Chen, Binbin Tao, Shaoting Jia, Zuoyan Zhu, Vance L TrudeauAbstract:γ-Aminobutyric acid (GABA) is a major amino acid neurotransmitter in the vertebrate brain. To provide detailed information on the distribution of the GABA in zebrafish (Danio rerio), neurons were labeled with mCherry driven by the glutamic acid decarboxylase 67 (gad67) promoter. In the transgenic line Tg(gad67:mCherry), mCherry-positive gad67 cell bodies were predominantly localized to the olfactory bulb, pallial zones, subpallium zones, parvocellular preoptic Nucleus, periventricular gray zone of optic tectum, torus semicircularis, posterior tuberculum, medial longitudinal fascicle, caudal zone of periventricular hypothalamus, and oculomotor Nucleus. mCherry-positive fibers were widely distributed in the olfactory bulbs, subpallium, thalamus, ventral hypothalamic zone, tectum opticum, mesencephalon, and rhombencephalon. mCherry-positive neurons were also observed in the retina and the spinal cord. The anatomical relationships between GABAergic and gonadotrophin-releasing hormone 3 (GnRH3) neurons were investigated by crossing Tg(gad67:mCherry) fish with the previously established Tg(gnrh3:EGFP) transgenic line. GnRH3 cell bodies and fibers were contacted by GABAergic fibers directly in the ventral telencephalon and anterior Tuberal Nucleus. A subpopulation of GnRH3 neurons in the ventral telencephalic area was also labeled with mCherry, so some GnRH3 neurons are also GABAergic. GABAB receptor agonist (baclofen) and antagonist (CGP55845) treatments indicated that GABAB receptor signaling inhibited gnrh3 expression in larval fish but was stimulatory in adult fish. The expression of pituitary lhβ and fshβ was stimulated by intraperitoneal injection of baclofen in adult fish. We conclude that GABA via GABAB receptors regulates GnRH3 neurons in a developmentally dependent manner in zebrafish.
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Forebrain mapping of secretoneurin-like immunoreactivity and its colocalization with isotocin in the preoptic Nucleus and pituitary gland of goldfish.
Journal of Comparative Neurology, 2011Co-Authors: Luis Fabián Canosa, G. C. Lopez, E. Scharrig, K. Lesaux-farmer, Gustavo Manuel Somoza, Vance L TrudeauAbstract:Secretoneurin, a 33-34 amino acid neuropeptide derived from the proteolytic processing of the secretogranin-II precursor protein, is reasonably well conserved in evolution. Goldfish secretoneurin shares >75% similarity overall with other vertebrate secretoneurin sequences. The secretoneurin peptide has numerous functions that include neuroinflammation, neurotransmitter release, and neuroendocrine regulation. A detailed description of the central distribution of secretoneurin immunoreactivity is only known for the rat. Using our polyclonal antibody against the central, conserved core of the secretoneurin peptide we studied the distribution of secretoneurin-like immunoreactivity in the goldfish brain. Secretoneurin immunoreactivity was found in the olfactory bulb, entopeduncular Nucleus, preoptic Nucleus, lateral part of the lateral Tuberal Nucleus, posterior periventricular Nucleus, Nucleus of the posterior recess, the Nucleus of the saccus vasculosus, and Nucleus isthmi. Secretoneurin-immunoreactive fibers were found in the dorsal part of the dorsal telencephalon, ventral and lateral parts of the ventral telencephalon, periventricular preoptic Nucleus, pituitary, and the ventrocaudal aspect of the Nucleus of the lateral recess. The most conspicuous secretoneurin immunoreactivity was found in the magnocellular and parvocellular cells of the preoptic Nucleus that project to the pituitary. Double-labeling studies indicated coexpression with isotocin, the fish homolog of mammalian oxytocin. Clear colabeling for secretoneurin and isotocin in fibers terminating in the neurointermediate lobe suggests that secretoneurin maybe coreleased with isotocin. Previous work indicates that secretoneurin stimulates the release of luteinizing hormone from the goldfish anterior pituitary. Our findings further support a reproductive role for secretoneurin and related peptides, given the importance of oxytocin family peptides in reproductive behavior in vertebrates.
M I Borella - One of the best experts on this subject based on the ideXlab platform.
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Distribution of GnRH in the brain of the freshwater teleost Astyanax altiparanae.
Micron (Oxford England : 1993), 2013Co-Authors: C C Gomes, F G Costa, M I BorellaAbstract:GnRH is well known as a key decapeptide neurohormone involved in reproduction, stimulating the pituitary gland to release gonadotropins (LH and FSH), which, in turn, regulate steroidogenesis and gametogenesis. However, in addition to its reproductive functions, GnRH displays neuromodulatory roles with implications for sexual behavior. The pattern of distribution in the brain of GnRH may help reveal GnRH specific functions. Therefore, the main emphasis of this study is to detect the presence and distribution of GnRH in the brain of the freshwater teleost Astyanax altiparanae ("lambari"). The immunohistochemical method of peroxidase with an antibody raised against GnRH3 was used to detect the location of GnRHs in the brain and pituitary gland. Immunoreactivity to GnRH was found in the following encephalic areas: olfactory bulb, terminal nerve ganglion, preoptic area, Nucleus of midbrain tegmentum, but also in torus longitudinalis, glomerular Nucleus, and central and dorsal posterior nuclei of dorsal thalamus. In addition, cell bodies from neurons in the parvocellular and magnocellular periventricular nuclei and ventral Tuberal Nucleus along with many fibers including ones innervating the neurohypophysis were immunoreactive to a GnRH antiserum that detects all known eight GnRH peptides in teleosts. This is the first study describing the distribution of the complete GnRH system in the brain of A. altiparanae, which has great importance for aquaculture and ecology, and represents one of the major orders of South American teleosts--the Characiformes.
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Distribution of GnRH in the brain of the freshwater teleost Astyanax altiparanae (Garutti & Britski, 2000)
Micron, 2013Co-Authors: C C Gomes, F G Costa, M I BorellaAbstract:Abstract GnRH is well known as a key decapeptide neurohormone involved in reproduction, stimulating the pituitary gland to release gonadotropins (LH and FSH), which, in turn, regulate steroidogenesis and gametogenesis. However, in addition to its reproductive functions, GnRH displays neuromodulatory roles with implications for sexual behavior. The pattern of distribution in the brain of GnRH may help reveal GnRH specific functions. Therefore, the main emphasis of this study is to detect the presence and distribution of GnRH in the brain of the freshwater teleost Astyanax altiparanae (“lambari”). The immunohistochemical method of peroxidase with an antibody raised against GnRH3 was used to detect the location of GnRHs in the brain and pituitary gland. Immunoreactivity to GnRH was found in the following encephalic areas: olfactory bulb, terminal nerve ganglion, preoptic area, Nucleus of midbrain tegmentum, but also in torus longitudinalis, glomerular Nucleus, and central and dorsal posterior nuclei of dorsal thalamus. In addition, cell bodies from neurons in the parvocellular and magnocellular periventricular nuclei and ventral Tuberal Nucleus along with many fibers including ones innervating the neurohypophysis were immunoreactive to a GnRH antiserum that detects all known eight GnRH peptides in teleosts. This is the first study describing the distribution of the complete GnRH system in the brain of A. altiparanae , which has great importance for aquaculture and ecology, and represents one of the major orders of South American teleosts – the Characiformes.
Julian Yanez - One of the best experts on this subject based on the ideXlab platform.
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Experimental study of the connections of the preglomerular nuclei and corpus mamillare in the rainbow trout, Oncorhynchus mykiss
Brain Research Bulletin, 2005Co-Authors: Monica Folgueira, Ramón Anadón, Julian YanezAbstract:The preglomerular complex of trout consists of the anterior (aPGN) and medial (mPGN) preglomerular nuclei and the corpus mamillare (CM). In order to improve knowledge on this complex, we applied a lipophilic neuronal tracer (DiI) to the three nuclei. These nuclei received afferents from the medial part of the dorsal telencephalic area (Dm), the ventral part of the ventral telencephalic area (Vv), the preoptic Nucleus, the periventricular layer of the rostral optic tectum and the central posterior thalamic Nucleus. The aPGN also received numerous toral projections and, sent efferents to the anterior Tuberal Nucleus. In addition, both the aPGN and the mPGN nuclei gave rise to efferents to the dorsal region of the dorsal telencephalic area (Dd), whereas the medial preglomerular Nucleus and the CM sent fibers to the torus lateralis and the diffuse Nucleus, as confirmed by reciprocal labeling. A small mPGN/CM subgroup projected to the optic tectum. These results suggest close functional inter-relationship between the trout preglomerular complex and two telencephalic regions (Dm and Vv). In addition, all nuclei of the complex receive preoptic, tectal and dorsal thalamic afferents, whereas the aPGN and mPGN are related with acoustic-lateral ascending pathways, and the mPGN and CM with the central region of the dorsal telencephalic area and visceral/gustatory pathways.
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experimental study of the connections of the telencephalon in the rainbow trout oncorhynchus mykiss ii dorsal area and preoptic region
The Journal of Comparative Neurology, 2004Co-Authors: Monica Folgueira, Ramón Anadón, Julian YanezAbstract:In this study and the accompanying article (Folgueira et al., 2004a), the fluorescent carbocyanine dye 1,1-dioctadecyl 3,3,3,3-tetramethylindocarbocyanine perchlorate (DiI) was used in fixed tissue to comprehensively analyze the connections of the different regions of the telencephalic lobes and the preoptic region of the rainbow trout. Here, we analyze the connections of the dorsal area (D; pallium) of the telencephalon, and the preoptic region, as well as the telencephalic connections of several structures in the diencephalon and brainstem of juvenile trout. The dorsal plus dorsolateral pallial zone of D (DdDl-d) receives afferents from contralateral DdDl-d, the ventral area of the telencephalon, preoptic Nucleus, suprachiasmatic Nucleus, medial thalamus, preglomerular complex, anterior and lateral Tuberal nuclei, posterior Tuberal Nucleus, posterior hypothalamic lobe, superior raphe Nucleus, and the rhombencephalic central gray and reticular formation, and projects to the central zone of D (Dc), medial thalamus, and some caudomedial hypothalamic regions. The medial zone of D (Dm) maintains reciprocal connections with the preglomerular complex and also receives afferents from the preoptic Nucleus, suprachiasmatic Nucleus, anterior Tuberal Nucleus, preglomerular tertiary gustatory Nucleus, posterior tubercle, superior raphe Nucleus, locus coeruleus, and the rhombencephalic central gray, and reticular formation. Dc receives fibers mainly from DdDl-d, preoptic Nucleus, preglomerular complex, and torus semicircularis and projects to several extratelencephalic centers, including the paracommissural Nucleus, optic tectum, torus semicircularis, thalamus, preglomerular complex, posterior tubercle nuclei, and inferior hypothalamic lobes. The posterior zone of D (Dp) is mainly connected with the olfactory bulbs, the ventral and supracommissural nuclei of the ventral area (subpallium), the preoptic Nucleus, and the preglomerular complex and projects to wide hypothalamic and posterior tubercular regions. The preoptic Nucleus projects to the olfactory bulb, to most regions of the telencephalic lobes, and to several diencephalic and brainstem structures. These results reveal complex and specialized connectional patterns in the rainbow trout dorsal telencephalon and preoptic region. Most of these connections have not been described previously in salmonids. These connections indicate that the salmonid telencephalon is involved in multisensorial processing and modulation of brain activity. J. Comp. Neurol. 480:204–233, 2004. © 2004 Wiley-Liss, Inc. Indexing terms: olfactory bulb; pallium; thalamus; torus semicircularis; cerebellum; teleost
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distribution of choline acetyltransferase chat immunoreactivity in the brain of the adult trout and tract tracing observations on the connections of the nuclei of the isthmus
The Journal of Comparative Neurology, 2000Co-Authors: Silvia Eva Perez, Ramón Anadón, Julian Yanez, Oscar Marin, Agustin Gonzalez, Isabel RodriguezmoldesAbstract:The distribution of cholinergic neurons and fibers was studied in the brain and rostral spinal cord of the brown trout and rainbow trout by using an antiserum against the enzyme choline acetyltransferase (ChAT). Cholinergic neurons were observed in the ventral telencephalon, preoptic region, habenula, thalamus, hypothalamus, magnocellular superficial pretectal Nucleus, optic tectum, isthmus, cranial nerve motor nuclei, and spinal cord. In addition, new cholinergic groups were detected in the vascular organ of the lamina terminalis, the parvocellular and magnocellular parts of the preoptic Nucleus, the anterior Tuberal Nucleus, and a mesencephalic tegmental Nucleus. The presence of ChAT in the magnocellular neurosecretory system of trout suggests that acetylcholine is involved in control of hormone release by neurosecretory terminals. In order to characterize the several cholinergic nuclei observed in the isthmus of trout, their projections were studied by application of 1,1;-dioctadecyl-3,3,3;, 3;-tetramethylindocarbocyanine perchlorate (DiI) to selected structures of the brain. The secondary gustatory Nucleus projected mainly to the lateral hypothalamic lobes, whereas the Nucleus isthmi projected to the optic tectum and parvocellular superficial pretectal Nucleus, as previously described in other teleost groups. In addition, other isthmic cholinergic nuclei of trout may be homologs of the mesopontine system of mammals. We conclude that the cholinergic systems of teleosts show many primitive features that have been preserved during evolution, together with characteristics exclusive to the group.
H P H Kremer - One of the best experts on this subject based on the ideXlab platform.
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somatostatin 1 12 immunoreactivity is decreased in the hypothalamic lateral Tuberal Nucleus of huntington s disease patients
Brain Research, 1996Co-Authors: H J L M Timmers, D F Swaab, H P H KremerAbstract:Abstract The hypothalamic lateral Tuberal Nucleus (NTL) can be recognized in man and higher primates, only. The function of this Nucleus is unknown, but the NTL is affected in a variety of human neurodegenerative diseases, including Huntington's disease (HD) and Alzheimer's disease. In the present study we demonstrate an abundant presence of somatostatin 1–12 (SSTI-12) immunoreactivity in both neurites and perikarya of the NTL. This immunoreactivity could be visualized best after microwave pretreatment. In HD brains, NTL SSTI-12 immunoreactivity was greatly reduced, providing further evidence of the presence of SSTI-12 as an intrinsic neuropeptide in the NTL. Although striatal SST neurons escape destruction in HD, our study demonstrates that not all SST neurons are resistant to the degenerative process in this disease.
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Lewy bodies in the lateral hypothalamus: Do they imply neuronal loss?
Movement disorders : official journal of the Movement Disorder Society, 1993Co-Authors: H P H Kremer, G. Th A. M. BotsAbstract:Lewy bodies have been found in the hypothalamic lateral Tuberal Nucleus (NTL) and the adjoining tuberomammillary Nucleus (TM) in Parkinson's disease (PD). The NTL is severely atrophic in Huntington's disease; the TM seems unaffected. In this study, we examined we examined the NTL and the TM of seven PD patients and one patient with presumed PD to assess whether the presence of Lewy bodies indicated neuronal loss. Most Lewy bodies were found in the TM, but they were also present in the NTL of seven of the eight patients. The number of NTL neurons in the PD patients was similar to a group of 14 nonneurological controls, seven Alzheimer's disease (AD) patients, and two AIDS patients with dementia. This challenges the hypothesis that Lewy bodies are a sign of significant cell death. The TM, whose cells could not be counted, did not seem depleted in neuronal numbers, although occasional neuronophagia was observed.
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Weight Loss in Huntington's Disease
Archives of neurology, 1992Co-Authors: H P H Kremer, Raymund A.c. RoosAbstract:To the Editor. —The article by Myers and coworkers1 presented interesting observations on Huntington's disease progression and its relationship to several clinical variables. Specifically, the authors found significant associations between progression rate and age at onset and body weight (body mass index) at initial examination; fatter patients or late-onset patients deteriorated slower. The authors refrain from offering a biological explanation, but we think that the following might be considered. Recently, we 2 described selective neuronal loss in the hypothalamic lateral Tuberal Nucleus (NTL) of patients with Huntington's disease. 2 The log-transformed number of remaining NTL neurons was closely correlated with age at onset of the disease (n = 16; r = .78; P 3 The function of this Nucleus, situated in the Tuberal part of the lateral hypothalamus, is unknown. In rodents, the lateral hypothalamic area (LHA) is involved in a large variety of behavioral and metabolic functions, eg, in the regulation
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The hypothalamic lateral Tuberal Nucleus: normal anatomy and changes in neurological diseases.
Progress in brain research, 1992Co-Authors: H P H KremerAbstract:The lateral Tuberal Nucleus is a circumscribed cell mass in the lateral posterior part of the hypothalamus, containing about 60000 neurons. It can be recognized in man and higher primates, probably not in other mammals. Its neurotransmitter content and connections with other parts of the brain are as yet unknown. But receptors for corticotropin-releasing factor and somatostatin, as well as muscarinic cholinergic receptors, benzodiazepine receptors and N-methyl-D-aspartate receptors have been localized within the confines of the Nucleus. The lateral Tuberal Nucleus is affected in a number of human neurodegenerative diseases. Changes in Parkinson's disease are the least obvious: Lewy bodies appear in small amounts, the majority of them apparently lying outside a neuronal perikaryon. Neuronal loss does not occur. In Alzheimer's disease the number of neurons seems to be normal as well. Rarely silver staining tangles occur, and the deposition of A4/beta-protein in amorphous plaques is moderate. Yet, NTL neurons stain heavily in Alz-50 immunocytochemistry, while Alz-50 staining in NTL neurites is very dense. These changes are interpreted as indicating early Alzheimer-related pathology. In Huntington's disease the NTL loses neurons. This loss is related to the severity of the disease: patients who first display motor disturbances at an early age will lose more neurons than those who start later. The relation between these clinical characteristics and the severity of neuronal loss is such, that it seems likely that NTL neurons possess a special vulnerability for the effect of the Huntington gene. This could be related to their NMDA-receptor content. It is hypothesized that the NTL is involved in a neuronal network that regulates feeding and metabolism. NTL pathology may explain the peculiar catabolic state of many patients with Alzheimer's or Huntington's diseases.
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the human hypothalamus in development sexual differentiation aging and alzheimer s disease
Progress in Brain Research, 1992Co-Authors: D F Swaab, H P H Kremer, Michel A. Hofman, E Goudsmit, Rivka RavidAbstract:Publisher Summary In this chapter, recent data on morphological alterations of several hypothalamic structures in normal development, sexual differentiation, aging, and Alzheimer's disease are reported. The sexually dimorphic Nucleus, the suprachiasmatic Nucleus, the supraoptic Nucleus, the paraventricular Nucleus, and the lateral Tuberal Nucleus have so far been studied with respect to the changes occurring in brain–endocrine interactions in the human hypothalamus during these conditions. Alzheimer's disease in many respects can be considered as an advanced, accelerated form of aging. During both conditions, activated neurons have a better chance for survival. The human hypothalamus is involved in a wide range of functions in the developing, adult and aging subject, as well as in various diseases of different etiologies. Alterations in hypothalamic structures and functions are thought to be operative in diseases such as anorexia nervosa, bulimia, depression, Cushing's disease, diabetes insipidus, Prader–Willi syndrome, polycystic ovaries syndrome and the malignant neuroleptic syndrome as well as in disturbances in sleep and temperature regulation. The hypothalamus is affected in neurodegenerative diseases and might be responsible for particular symptoms—for example, in Alzheimer's, Parkinson's and Huntington's disease and possibly in multiple sclerosis.
