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1.
Front Neural Circuits ; 12: 86, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30364230

RESUMO

Limbic brain regions drive goal-directed behaviors. These behaviors often require dynamic motor responses, but the functional connectome of limbic structures in the diencephalon that control locomotion is not well known. The A11 region, within the posterior diencephalon has been postulated to contribute to motor function and control of pain. Here we show that the A11 region initiates movement. Photostimulation of channelrhodopsin 2 (ChR2) transfected neurons in A11 slice preparations showed that neurons could follow stimulation at frequencies of 20 Hz. Our data show that photostimulation of ChR2 transfected neurons in the A11 region enhances motor activity often leading to locomotion. Using vGluT2-reporter and vGAT-reporter mice we show that the A11 tyrosine hydroxylase positive (TH) dopaminergic neurons are vGluT2 and vGAT negative. We find that in addition to dopaminergic neurons within the A11 region, there is another neuronal subtype which expresses the monoenzymatic aromatic L-amino acid decarboxylase (AADC), but not TH, a key enzyme involved in the synthesis of catecholamines including dopamine. This monoaminergic-based motor circuit may be involved in the control of motor behavior as part of a broader diencephalic motor region.


Assuntos
Diencéfalo/química , Diencéfalo/fisiologia , Atividade Motora/fisiologia , Optogenética/métodos , Estimulação Luminosa/métodos , Animais , Feminino , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos
2.
Folia Histochem Cytobiol ; 56(1): 49-58, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29516445

RESUMO

INTRODUCTION: The distribution of the immunoreactive cell bodies and fibers containing neurotensin in the alpaca diencephalon was determined by an immunohistochemical technique. MATERIAL AND METHODS: The study was carried out in four male alpacas that lived at sea level. Brains of deeply anesthetized animals were fixed by perfusion with 4% paraformaldehyde. Cryostat sections were stained by a standard immunohistochemical method. RESULTS: Cell bodies containing neurotensin were observed in the zona incerta and hypothalamus. A low/moderate density of these cell bodies was observed in the lateral hypothalamic area, anterior and dorsal hypothalamic areas, suprachiasmatic nucleus, periventricular region of the hypothalamus and in the ventromedial hypothalamic nucleus. In both thalamus and hypothalamus, immunoreactive fibers showed a widespread distribution. In the thalamus, a high density of these fibers was mainly found in the midline nuclei, whereas in the hypothalamus a high density was in general observed in the whole structure. CONCLUSIONS: In comparison with other mammals, the thalamus of the alpaca showed the most widespread distribution of neurotensin-immunoreactive fibers. The widespread distribution of neurotensin through the alpaca diencephalon suggests that the peptide can be involved in many physiological actions.


Assuntos
Camelídeos Americanos , Diencéfalo/metabolismo , Neurotensina/metabolismo , Animais , Corpo Celular/química , Corpo Celular/metabolismo , Diencéfalo/química , Hipotálamo/química , Hipotálamo/metabolismo , Imuno-Histoquímica , Masculino , Neurotensina/química
3.
Age (Dordr) ; 35(3): 821-37, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22648398

RESUMO

Estrogens are not only critical for sexual differentiation it is well-known for the role of 17ß-estradiol (E2) in the adult brain modulating memory, learning, mood and acts as a neuroprotector. E2 exerts its actions through two classical receptors: estrogen receptor alpha (ERα) and estrogen receptor beta (ERß). The distribution of both receptors changes from one brain area to another, E2 being able to modulate their expression. Among the classical features of aging in humans, we find cognitive impairment, dementia, memory loss, etc. As estrogen levels change with age, especially in females, it is important to know the effects of low E2 levels on ERα distribution; results from previous studies are controversial regarding this issue. In the present work, we have studied the effects of long-term E2 depletion as well as the ones of E2 treatment on ERα brain distribution of ovariectomized rats along aging in the diencephalon and in the telencephalon. We have found that ovariectomy causes downregulation and affects subcellular localization of ERα expression during aging, meanwhile prolonged estrogen treatment produces upregulation and overexpression of the receptor levels. Our results support the idea of the region-specific neuroprotection mechanisms mediated by estradiol.


Assuntos
Envelhecimento/metabolismo , Química Encefálica/fisiologia , Encéfalo/metabolismo , Estradiol/farmacologia , Receptor alfa de Estrogênio/metabolismo , Terapia de Reposição Hormonal , Espaço Intracelular/metabolismo , Envelhecimento/efeitos dos fármacos , Animais , Encéfalo/citologia , Encéfalo/efeitos dos fármacos , Córtex Cerebral/química , Córtex Cerebral/citologia , Densitometria , Diencéfalo/química , Diencéfalo/citologia , Diencéfalo/efeitos dos fármacos , Estrogênios/farmacologia , Feminino , Imuno-Histoquímica , Espaço Intracelular/efeitos dos fármacos , Ratos , Ratos Wistar , Telencéfalo/química , Telencéfalo/citologia , Telencéfalo/efeitos dos fármacos
4.
Cell Tissue Res ; 342(3): 437-57, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21079998

RESUMO

The distribution of three types of arginine vasotocin (AVT) receptors in the brain and pituitary of the newt Cynops pyrrhogaster, namely, the V1a-, V2-, and V3/V1b-type receptors, was studied by means of in situ hybridization and immunohistochemistry. mRNA signals and immunoreactive cells for the V1a-type receptor were observed in the telencephalon (mitral layer of the olfactory bulb, dorsal and medial pallium, lateral and medial amygdala, bed nucleus of the decussation of the fasciculus telencephali, bed nucleus of the stria terminalis), diencephalon (anterior preoptic area, magnocellular preoptic nucleus, suprachiasmatic nucleus, ventral thalamus, dorsal and ventral hypothalamic nucleus), mesencephalon (tegmentum, interpeduncular nucleus), and medulla oblongata (median reticular formation, nucleus motorius tegmenti). Cells expressing the V2-type receptor were found in the telencephalon (medial pallium, lateral and medial amygdala, bed nucleus of the decussation of the fasciculus telencephali), and mesencephalon (tegmentum trigemini and facialis). In the paraphysis (possibly the main site of cerebrospinal fluid production), only V2-type receptor mRNA signal and immunoreactivity were detected. V3/V1b-type receptor mRNA was expressed in the diencephalon (dorsal hypothalamic nucleus, nucleus tuberculi posterioris), mesencephalon (tegmentum, interpeduncular nucleus), and medulla oblongata (raphe nucleus), whereas V3/V1b-type-receptor-like immunoreactivity was scarcely detectable in the entire brain. The V3/V1b-type receptor was predominantly expressed in the anterior pituitary. V3/V1b-type receptor and proopiomelanocortin mRNAs were co-localized in the distal lobe of the pituitary. This is the first report of the distribution of three types of AVT receptor in the brain and pituitary of non-mammalian vertebrates.


Assuntos
Química Encefálica , Adeno-Hipófise/química , Adeno-Hipófise/citologia , Receptores de Vasopressinas/análise , Salamandridae/metabolismo , Animais , Diencéfalo/química , Diencéfalo/citologia , Imunofluorescência , Hibridização In Situ , Bulbo/química , Bulbo/citologia , Mesencéfalo/química , Mesencéfalo/citologia , Reação em Cadeia da Polimerase , RNA Mensageiro , Receptores de Vasopressinas/isolamento & purificação , Transdução de Sinais , Telencéfalo/química , Telencéfalo/citologia
5.
Dev Dyn ; 239(8): 2298-306, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20658694

RESUMO

The Dlx genes encode a family of transcription factors important for the development of the vertebrate forebrain. These genes have very similar expression domains during the development of the telencephalon in mice and play a role in gamma-aminobutyric acid (GABAergic) interneuron differentiation. We have used triple fluorescent in situ hybridization to study the relative expression domains of the dlx and gad1 genes in the zebrafish telencephalon and diencephalon. We also generated transgenic zebrafish with regulatory elements from the zebrafish dlx1a/2a locus. The zebrafish dlx regulatory elements recapitulated dlx expression in the forebrain and mimicked the relationship between the expression of the dlx genes and gad1. Finally, we show that a putative enhancer located downstream of dlx2b can also activate reporter gene expression in a tissue-specific manner similar to endogenous dlx2b expression. Our results indicate the dlx genes are regulated by an evolutionarily conserved genetic pathway and may play a role in GABAergic interneuron differentiation in the zebrafish forebrain.


Assuntos
Glutamato Descarboxilase/análise , Proteínas de Homeodomínio/análise , Prosencéfalo/metabolismo , Fatores de Transcrição/análise , Animais , Diencéfalo/química , Hibridização in Situ Fluorescente , Interneurônios/citologia , Organismos Geneticamente Modificados , Prosencéfalo/crescimento & desenvolvimento , Telencéfalo/química , Peixe-Zebra , Ácido gama-Aminobutírico
6.
BMC Dev Biol ; 10: 30, 2010 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-20298575

RESUMO

BACKGROUND: Endogenous peptides such as neuropeptides are involved in numerous biological processes in the fully developed brain but very little is known about their role in brain development. Japanese quail is a commonly used bird model for studying sexual dimorphic brain development, especially adult male copulatory behavior in relation to manipulations of the embryonic endocrine system. This study uses a label-free liquid chromatography mass spectrometry approach to analyze the influence of age (embryonic days 12 vs 17), sex and embryonic day 3 ethinylestradiol exposure on the expression of multiple endogenous peptides in the developing diencephalon. RESULTS: We identified a total of 65 peptides whereof 38 were sufficiently present in all groups for statistical analysis. Age was the most defining variable in the data and sex had the least impact. Most identified peptides were more highly expressed in embryonic day 17. The top candidates for EE2 exposure and sex effects were neuropeptide K (downregulated by EE2 in males and females), gastrin-releasing peptide (more highly expressed in control and EE2 exposed males) and gonadotropin-inhibiting hormone related protein 2 (more highly expressed in control males and displaying interaction effects between age and sex). We also report a new potential secretogranin-2 derived neuropeptide and previously unknown phosphorylations in the C-terminal flanking protachykinin 1 neuropeptide. CONCLUSIONS: This study is the first larger study on endogenous peptides in the developing brain and implies a previously unknown role for a number of neuropeptides in middle to late avian embryogenesis. It demonstrates the power of label-free liquid chromatography mass spectrometry to analyze the expression of multiple endogenous peptides and the potential to detect new putative peptide candidates in a developmental model.


Assuntos
Coturnix/embriologia , Diencéfalo/química , Diencéfalo/embriologia , Regulação da Expressão Gênica no Desenvolvimento , Neuropeptídeos/análise , Animais , Cromatografia Líquida , Coturnix/genética , Coturnix/metabolismo , Diencéfalo/metabolismo , Embrião não Mamífero/metabolismo , Desenvolvimento Embrionário , Feminino , Masculino , Espectrometria de Massas , Neuropeptídeos/genética , Caracteres Sexuais
7.
Artigo em Inglês | MEDLINE | ID: mdl-19539045

RESUMO

Nitric oxide (NO) plays a key role in body temperature (Tb) regulation of mammals, acting on the brain to stimulate heat loss. Regarding birds, the putative participation of NO in the maintenance of Tb in thermoneutrality or during heat stress and the site of its action (periphery or brain) is unknown. Thus, we tested if NO participates in the maintenance of chicks' Tb in those conditions. We investigated the effect of intramuscular (im; 25, 50, 100mg/kg) or intracerebroventricular (icv; 22.5, 45, 90, 180 microg/animal) injections of the non selective NO synthase inhibitor L-NAME on Tb of 5-day-old chicks at thermoneutral zone (TNZ; 31-32 degrees C) and under heat stress (37 degrees C for 5-6h). We also verified plasma and diencephalic nitrite/nitrate levels in non-injected chicks under both conditions. At TNZ, 100mg/kg (im) or 45, 90, 180 microg (icv) of L-NAME decreased Tb. A significant correlation between Tb and diencephalic, but not plasma, nitrite/nitrate levels was observed. Heat stress-induced hyperthermia was inhibited by all tested doses of L-NAME (im and icv). Tb was correlated neither with plasma nor with diencephalic nitrite/nitrate levels during heat stress. These results indicate the involvement of brain NO in the maintenance of Tb of chicks, an opposite action of that observed in mammals, and may modulate hyperthermia.


Assuntos
Regulação da Temperatura Corporal/fisiologia , Galinhas/fisiologia , Diencéfalo/química , Óxido Nítrico Sintase/metabolismo , Óxido Nítrico/fisiologia , Animais , Galinhas/crescimento & desenvolvimento , Diencéfalo/enzimologia , Relação Dose-Resposta a Droga , Inibidores Enzimáticos/administração & dosagem , Inibidores Enzimáticos/farmacologia , Temperatura Alta/efeitos adversos , Injeções Intraventriculares , Masculino , NG-Nitroarginina Metil Éster/administração & dosagem , NG-Nitroarginina Metil Éster/farmacologia , Nitratos/análise , Nitratos/sangue , Óxido Nítrico Sintase/antagonistas & inibidores , Nitritos/análise , Nitritos/sangue , Estresse Fisiológico/fisiologia
8.
Neuropeptides ; 43(2): 63-71, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19261328

RESUMO

Orexin-induced orexigenic action is mediated by neuropeptide Y (NPY) in goldfish and rodents. A previous study indicated that NPY-induced orexigenic action may also be mediated by orexin-A in goldfish. However, there is little information about the mutual actions of orexin-A and NPY in the goldfish. Therefore, using their specific receptor antagonists, we examined whether the orexigenic actions of orexin-A and NPY mutually interact in the goldfish. The stimulatory effect of intracerebroventricular injection of NPY at 1 pmol/g body weight (BW) on food intake was abolished by treatment with the orexin receptor-1 antagonist, SB334867, at 10 pmol/g BW whereas the NPY Y1-receptor antagonist, BIBP3226, at 100 pmol/g BW attenuated orexin-A (at 2.8 pmol/g BW)-stimulated feeding. This led us, using a double-immunostaining method and confocal laser scanning microscopy, to investigate whether orexin-A- and NPY-containing neurons in the goldfish brain have direct mutual inputs. Orexin-A- and NPY-like immunoreactivities were distributed throughout the brain, especially in the diencephalon. Orexin-A- and NPY-containing neurons were located in a region of the hypothalamus, the nucleus posterioris periventricularis (NPPv), in close proximity to each other: NPY-containing nerve fibers or endings lay in close apposition to orexin-A-containing neurons in the NPPv, and orexin-A-containing nerve fibers or endings also lay in close apposition to NPY-containing neurons in the same region. These results indicate that, in goldfish, orexin-A- and NPY-induced orexigenic actions are mediated by mutual signaling pathways.


Assuntos
Ingestão de Alimentos/efeitos dos fármacos , Peptídeos e Proteínas de Sinalização Intracelular/análise , Neurônios/química , Neuropeptídeo Y/análise , Neuropeptídeo Y/farmacologia , Neuropeptídeos/análise , Animais , Encéfalo/citologia , Diencéfalo/química , Carpa Dourada , Hipotálamo/química , Orexinas , Transdução de Sinais , Simpatomiméticos/análise
9.
Eur J Histochem ; 52(1): 19-28, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18502719

RESUMO

The present study was focused on the morphology of the diencephalic nuclei (likely involved in reproductive functions) as well as on the distribution of GnRH (gonadotropin-releasing hormone) in the rhinencephalon, telencephalon and the diencephalon of the brain of bluefin tuna (Thunnus thynnus) by means of immunohistochemistry. Bluefin tuna has an encephalization quotient (QE) similar to that of other large pelagic fish. Its brain exhibits well-developed optic tecta and corpus cerebelli. The diencephalic neuron cell bodies involved in reproductive functions are grouped in two main nuclei: the nucleus preopticus-periventricularis and the nucleus lateralis tuberis. The nucleus preopticus-periventricularis consists of the nucleus periventricularis and the nucleus preopticus consisting of a few sparse multipolar neurons in the rostral part and numerous cells closely packed and arranged in several layers in its aboral part. The nucleus lateralis tuberis is located in the ventral-lateral area of the diencephalon and is made up of a number of large multipolar neurones. Four different polyclonal primary antibodies against salmon (s)GnRH, chicken (c)GnRH-II (cGnRH-II 675, cGnRH-II 6) and sea bream (sb)GnRH were employed in the immunohistochemical experiments. No immunoreactive structures were found with anti sbGnRH serum. sGnRH and cGnRH-II antisera revealed immunoreactivity in the perikarya of the olfactory bulbs, preopticus-periventricular nucleus, oculomotor nucleus and midbrain tegmentum. The nucleus lateralis tuberis showed immunostaining only with anti-sGnRH serum. Nerve fibres immunoreactive to cGnRH and sGnRH sera were found in the olfactory bulbs, olfactory nerve and neurohypophysis. The significance of the distribution of the GnRH-immunoreactive neuronal structures is discussed.


Assuntos
Química Encefálica , Encéfalo/anatomia & histologia , Hormônio Liberador de Gonadotropina/análise , Atum/anatomia & histologia , Atum/metabolismo , Animais , Diencéfalo/química , Imuno-Histoquímica , Neurônios/química , Condutos Olfatórios/química , Telencéfalo/química
10.
Gen Comp Endocrinol ; 149(3): 269-77, 2006 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-16860322

RESUMO

The distribution of galanin-like immunoreactive perikarya and nerve fibers in the brain of the snake Bothrops jararaca was studied by means of immunohistochemistry using an antiserum against porcine galanin. Immunoreactive neurons were only detected in the infundibular recess nucleus. Immunoreactive fibers were found in the telencephalic, diencephalic and mesencephalic areas such as the dorsal cortex, nucleus accumbens, lamina terminalis, preoptic area, mediodorsal region of the supraoptic nucleus, subfornical organ, nucleus of the paraventricular organ, subcommisural organ and periventricular grey region. The habenula, paraventricular nucleus, infundibular recess nucleus and hypothalamo-hypophyseal tract presented denser innervations. The outer layer of the median eminence displayed numerous fibers located close to the portal system, while scarce fibers were seen in the inner median eminence and neural lobe of the hypophysis. The distribution of labelled neurons in the brain of this snake was more restricted than that described in a turtle. The wide hypothalamic and extrahypothalamic distribution of labelled fibers suggests that galanin peptides may have hypophysiotropic, neuromodulator and neurotransmitter roles in the snake B. jararaca.


Assuntos
Bothrops/fisiologia , Química Encefálica , Galanina/análise , Animais , Tronco Encefálico/química , Diencéfalo/química , Feminino , Galanina/imunologia , Imuno-Histoquímica , Masculino , Neurônios/química , Telencéfalo/química
11.
Gen Comp Endocrinol ; 145(3): 270-9, 2006 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-16288754

RESUMO

The distribution of perikarya and fibers containing somatostatin was studied in the brain of the snake Bothrops jararaca by means of immunohistochemistry using an antiserum against synthetic somatostatin. Immunoreactive perikarya and fibers were localized in telencephalic, diencephalic and mesencephalic areas. In the telencephalon, numerous immunoreactive perikarya were found in the medial, dorsomedial, dorsal and lateral cortex, mainly in the deep plexiform layer, less so in the cellular layer, but not in the superficial plexiform layer. Immunoreactive perikarya were also observed in the dorsal ventricular ridge, the nucleus of the diagonal band of Broca, amygdaloid complex, septum and lamina terminalis. In the diencephalon, labelled cells were observed in the paraventricular, periventricular hypothalamic and in the recessus infundibular nuclei. In the mesencephalon, immunoreactive perikarya were seen in the mesencephalic reticular formation, reticular nucleus of the isthmus and torus semicircularis. Labelled fibers ran along the diencephalic floor and the inner zone of the median eminence, and ended in the neural lobe of the hypophysis. Other fibers were observed in the outer zone of the median eminence close to the portal vessels and in the septum, lamina terminalis, retrochiasmatic nucleus, deep layers of the tectum, periventricular gray and granular layer of the cerebellum. Our data suggest that somatostatin may function as a mediator of adenohypophysial secretion as well as neurotransmitter and/or neuromodulator which can regulate the neurohypophysial peptides in the snake B. jararaca.


Assuntos
Bothrops/metabolismo , Somatostatina/análise , Animais , Núcleo Arqueado do Hipotálamo/química , Química Encefálica , Córtex Cerebral/química , Diencéfalo/química , Epêndima/química , Epêndima/citologia , Feminino , Lobo Frontal/química , Imuno-Histoquímica , Masculino , Mesencéfalo/química , Núcleos da Linha Média do Tálamo/química , Fibras Nervosas/química , Núcleo Hipotalâmico Paraventricular/química , Telencéfalo/química
12.
J Neuroimmunol ; 159(1-2): 20-30, 2005 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-15652399

RESUMO

Serotonin (5-HT) is involved in neuroimmunomodulation. We analyzed the effects of sumatriptan, a 5-HT(1B/1D) receptor agonist, and ondansetron, a 5-HT(3) receptor antagonist, on thalamic mast cell (TMC) population, the only immunocytes known to infiltrate the brain in physiological conditions. Only sumatriptan was effective, significantly increasing TMC numbers versus controls, and especially those containing 5-HT. 5-HT(1B) receptors are concentrated in the median eminence on non-serotonergic axonal endings, probably hypothalamic terminal fibers, involved in hypothalamic-pituitary neuroendocrine modulating processes. TMC variations could reflect serotonergic actions on these fibers. TMCs would thus be cellular interfaces mediating immune action in the nervous system in relation with the hormonal status of the organism.


Assuntos
Movimento Celular/fisiologia , Mastócitos/citologia , Mastócitos/fisiologia , Serotonina/fisiologia , Tálamo/citologia , Tálamo/fisiologia , Animais , Degranulação Celular/efeitos dos fármacos , Movimento Celular/efeitos dos fármacos , Diencéfalo/química , Diencéfalo/citologia , Diencéfalo/efeitos dos fármacos , Diencéfalo/fisiologia , Imuno-Histoquímica , Masculino , Mastócitos/química , Mastócitos/efeitos dos fármacos , Microscopia de Fluorescência por Excitação Multifotônica , Ondansetron/administração & dosagem , Ratos , Ratos Sprague-Dawley , Receptor 5-HT1B de Serotonina/análise , Serotonina/análise , Agonistas do Receptor 5-HT1 de Serotonina , Sumatriptana/administração & dosagem , Tálamo/química
13.
Neuroscience ; 127(4): 921-8, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15312904

RESUMO

The organization of the efferent projections from the spinal trigeminal nucleus oralis (Sp5O) to the diencephalon was studied in the rat using the anterograde tracer Phaseolus vulgaris leucoagglutinin. The present study confirms the existence of trigemino-thalamic pathways originating from the Sp5O and details their distribution. The main diencephalic targets of the Sp5O are the ventral posteromedial thalamic nucleus (VPM), the posterior thalamic nuclei (Po) and the ventral part of the zona incerta (ZIv), contralaterally, and the parvicellular part of the ventral posterior thalamic nucleus (VPpc), bilaterally. The distribution of these projections varies according to the dorso-ventral location of the injection sites: the dorsal part of the Sp5O projects to the medial part of the VPM and the Po, and to the caudal part of the ZIv, as well as to the VPpc. The ventral part of the Sp5O projects to the lateral part of the VPM and the Po and to the rostral part of the ZIv. These results suggest that the trigemino-diencephalic pathways originating from the Sp5O are involved in the processing of gustatory and somatosensory information.


Assuntos
Diencéfalo/química , Diencéfalo/fisiologia , Núcleo Espinal do Trigêmeo/química , Núcleo Espinal do Trigêmeo/fisiologia , Animais , Masculino , Vias Neurais/química , Vias Neurais/fisiologia , Phaseolus/química , Ratos , Ratos Sprague-Dawley , Coloração e Rotulagem/métodos
14.
J Endocrinol ; 178(2): 311-8, 2003 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-12904178

RESUMO

We previously isolated a novel dodecapeptide containing a C-terminal -Arg-Phe-NH(2) sequence, SIKPSAYLPLRF-NH(2) (RFamide peptide), from the Japanese quail (Coturnix japonica) brain. This novel quail peptide was shown to be located in neurons of the paraventricular nucleus (PVN) and their terminals in the median eminence (ME), and to decrease gonadotropin release from cultured anterior pituitary in adult birds. We therefore designated this peptide gonadotropin-inhibitory hormone (GnIH). Furthermore, a cDNA encoding the GnIH precursor polypeptide has been characterized. To understand the physiological roles of this peptide, in the present study we analyzed developmental changes in the expressions of GnIH precursor mRNA and the mature peptide GnIH during embryonic and posthatch ages in the quail diencephalon including the PVN and ME. GnIH precursor mRNA was expressed in the diencephalon on embryonic day 10 (E10) and showed a significant increase on E17, just before hatch. GnIH was also detected in the diencephalon on E10 and increased significantly around hatch. Subsequently, the diencephalic GnIH content decreased temporarily, and again increased progressively until adulthood. GnIH-like immunoreactive (GnIH-ir) neurons were localized in the PVN on E10, but GnIH-ir fibers did not extend to the ME. However, GnIH-ir neurons increased in the PVN on E17, just before hatch, and GnIH-ir fibers extended to the external layer of the ME, as in adulthood. These results suggest that GnIH begins its function around hatch and acts as a hypothalamic factor to regulate gonadotropin release in the bird.


Assuntos
Proteínas Aviárias , Coturnix/crescimento & desenvolvimento , Coturnix/metabolismo , Hormônios Hipotalâmicos/metabolismo , Sistema Hipotálamo-Hipofisário/metabolismo , Neurônios/metabolismo , Precursores de RNA/análise , Animais , Diencéfalo/química , Ensaio de Imunoadsorção Enzimática/métodos , Feminino , Expressão Gênica , Idade Gestacional , Hormônios Hipotalâmicos/genética , Imuno-Histoquímica/métodos , Masculino , Eminência Mediana/química , Núcleo Hipotalâmico Paraventricular/química , Reação em Cadeia da Polimerase/métodos , RNA Mensageiro/análise
15.
Microsc Res Tech ; 59(6): 474-83, 2002 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-12467022

RESUMO

This review summarizes our recent studies using the viral transneuronal tracing technique to identify sites in the central nervous system (CNS) that are connected with the ovary. A neurotropic virus (pseudorabies virus) was injected into the ovary and various times after the inoculation the spinal cord and brain were examined for virus-infected neurons identified by immunocytochemistry. Such neurons could be detected in well-defined cell groups of the spinal cord (intermediolateral cell column), brain stem (vagal nuclei, area postrema, parapyramidal nucleus, caudal raphe nuclei, A1, A5, A7 noradrenergic cell groups, locus coeruleus, Barrington's nucleus, periaqueductal gray), hypothalamus (paraventricular nucleus, anterior hypothalamus, arcuate nucleus, zona incerta), and, at longer survival time, in some telencephalic structures (amygdala, bed nucleus of the stria terminalis). These findings provided the first neuromorphological evidence for the existence of a multisynaptic neuronal pathway between the brain and the ovary presumably involved in the neuronal control of the organ. The observations indicate that there is a significant overlap of CNS structures connected with the ovary, the testis, other organs and organ systems, suggesting similar neuronal circuitries of the autonomic nervous system innervating the different organs. The known descending neuronal connections between the CNS structures labeled from the ovary by the viral transneuronal tracing technique and the findings suggesting a pituitary independent interplay between certain cerebral structures such as the hypothalamus, the amygdala, and the ovary are also summarized in this review.


Assuntos
Sistema Nervoso Central/fisiologia , Glândulas Endócrinas/fisiologia , Ovário/inervação , Animais , Encéfalo/anatomia & histologia , Encéfalo/virologia , Sistema Nervoso Central/anatomia & histologia , Diencéfalo/química , Diencéfalo/virologia , Glândulas Endócrinas/anatomia & histologia , Glândulas Endócrinas/inervação , Feminino , Humanos , Telencéfalo/química , Telencéfalo/virologia
16.
Brain Res ; 948(1-2): 180-5, 2002 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-12383973

RESUMO

We have demonstrated that the quail brain possesses the cholesterol side-chain cleavage enzyme (cytochrome P450scc) and 3beta-hydroxysteroid dehydrogenase/delta(5)-delta(4)-isomerase (3beta-HSD) and produces pregnenolone, pregnenolone sulfate and progesterone from cholesterol. We have also demonstrated the expression of cytochrome P450 17alpha-hydroxylase/c17,20-lyase (P450(17alpha,lyase)) and the conversion of progesterone to 17alpha-hydroxyprogesterone in the same avian species. Therefore, the present study was conducted to investigate androgen biosynthesis from progesterone in the avian brain. Employing biochemical techniques combined with HPLC and TLC analyses, the conversion of progesterone to androstenedione, an androgen precursor, was found in quail brain. The present biochemical analysis further revealed the conversion of androstenedione to testosterone, indicating the presence of 17beta-hydroxysteroid dehydrogenase (17beta-HSD) in the quail brain. The formation of testosterone from progesterone was also detected in the brain. Testosterone formation was more intense in the diencephalon, whereas the concentration of endogenous testosterone in the diencephalon was lower than those in other brain regions in castrated quails. However, the concentration of endogenous estradiol, a metabolite of testosterone by cytochrome P450arom, was highest in the diencephalon of castrated quails. These results suggest that testosterone biosynthesis occurs in the quail brain, in particular the diencephalon. Testosterone may subsequently be converted to estradiol.


Assuntos
Androgênios/biossíntese , Encéfalo/metabolismo , Coturnix/metabolismo , 17-Hidroxiesteroide Desidrogenases/metabolismo , Androstenodiona/análise , Androstenodiona/metabolismo , Animais , Aromatase/metabolismo , Química Encefálica , Cerebelo/química , Cerebelo/metabolismo , Cromatografia Líquida de Alta Pressão , Cromatografia em Camada Fina , Diencéfalo/química , Diencéfalo/metabolismo , Estradiol/análise , Estradiol/metabolismo , Masculino , Mesencéfalo/química , Mesencéfalo/metabolismo , Orquiectomia , Progesterona/análise , Progesterona/metabolismo , Telencéfalo/química , Telencéfalo/metabolismo , Testosterona/análise , Testosterona/biossíntese , Testosterona/metabolismo
17.
J Comp Neurol ; 449(4): 374-89, 2002 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-12115673

RESUMO

This report describes the distribution of tyrosine hydroxylase (TH)-expressing structures in the brain of rainbow trout (Oncorhynchus mykiss). TH neurons have been localized by the use of two complementary techniques, immunocytochemistry and in situ hybridization of TH messenger RNA. Results obtained from in situ hybridization and immunocytochemistry were in agreement. TH cells were observed in many areas of the brain, with a higher density at the level of the olfactory bulbs where TH-positive neurons are abundant in the internal cell layer. In the telencephalon, two populations of TH neurons can be distinguished: one group is located in the area ventralis telencephali pars dorsalis, and the other group is located in the area ventralis telencephali pars ventralis and extends laterally in the area ventralis telencephali pars lateralis. Many labeled neurons are also seen in the preoptic area as well as in the hypothalamus, where several clusters of TH-positive cells are observed. Some of these neurons located in the paraventricular organ grow a short cytoplasmic extension directed to the ventricular wall and are known to be cerebrospinal fluid-contacting cells. The most caudal TH neurons are observed at the level of the locus caeruleus. At the level of the pituitary, TH-positive fibers are observed in the neurohypophysis. The TH-immunoreactive innervation at the level of the pituitary provides a neuroanatomic basis for the effects of dopamine and/or norepinephrine on the release of pituitary hormones in fish.


Assuntos
Química Encefálica , Encéfalo/enzimologia , RNA Mensageiro/metabolismo , Tirosina 3-Mono-Oxigenase/metabolismo , Animais , Encéfalo/citologia , Química Encefálica/genética , Química Encefálica/fisiologia , Tronco Encefálico/química , Tronco Encefálico/citologia , Tronco Encefálico/enzimologia , Diencéfalo/química , Diencéfalo/citologia , Diencéfalo/enzimologia , Feminino , Imuno-Histoquímica , Hibridização In Situ , Neurônios/química , Neurônios/citologia , Neurônios/enzimologia , Oncorhynchus mykiss , RNA Mensageiro/biossíntese , Telencéfalo/química , Telencéfalo/citologia , Telencéfalo/enzimologia , Tirosina 3-Mono-Oxigenase/biossíntese
18.
Gen Comp Endocrinol ; 126(2): 200-12, 2002 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-12030776

RESUMO

Using antisera directed against carp growth hormone-releasing hormone (cGHRH), we found more extensive brain distribution of GHRH-like immunoreactive (ir) neurons in the tiger frog, Rana tigrina, than reported in previous studies, which employed mammalian GHRH antibodies. In the telencephalon, GHRH-ir perikarya were present in the pallium dorsale, pallium laterale (pars dorsalis and pars ventralis), pallium mediale, nucleus entopeduncularis, amygdala pars medialis, and in the ventral portion of the lateral preoptic area. Most GHRH somata were present in the nucleus infundibularis ventralis located around the third ventricle, extending from the region posterior to the optic chiasma to the caudal end of infundibulum. In the thalamic region, GHRH-ir perikarya occurred in the area ventrolateralis thalami, the nuclei posterocentralis thalami, and the posterolateralis thalami. The ir cell bodies in the nucleus posteroventralis tegmenti mesencephali represented the caudal-most brain GHRH perikarya. Extensive GHRH-ir fibers occurred around the nonreactive cells in the ventral preoptic area and ventral area of the infundibulum. GHRH-ir fibers were present in the outer layers of the median eminence, but not in the neural lobe or pars distalis of the pituitary gland. This wider neuroanatomical distribution of GHRH-like peptide in the brain of R. tigrina should, provide the basis for future studies to establish the exact role of GHRH-like peptides in anuran brain.


Assuntos
Química Encefálica , Hormônio Liberador de Hormônio do Crescimento/análise , Imuno-Histoquímica , Ranidae/metabolismo , Animais , Especificidade de Anticorpos , Diencéfalo/química , Feminino , Masculino , Mesencéfalo/química , Telencéfalo/química , Distribuição Tecidual
19.
Fiziol Zh (1994) ; 48(6): 54-9, 2002.
Artigo em Ucraniano | MEDLINE | ID: mdl-12577470

RESUMO

In experiments on rats the influence of acupuncture on the lipid peroxidation processes and activities of the antioxidant systems in the gastric mucous membrane, the diencephalon and blood serum at ulcer processes in the gastroduodenal region were studied. It has been determined that acupuncture prevented mainly brain structures from the formation and accumulation of the products of lipid peroxidation that confirmed the neurogumoral influence of acupuncture on the central and peripheral links of ulcer genesis.


Assuntos
Terapia por Acupuntura , Peroxidação de Lipídeos/fisiologia , Estresse Oxidativo/fisiologia , Úlcera Péptica/terapia , Animais , Diencéfalo/química , Modelos Animais de Doenças , Mucosa Gástrica/química , Peróxidos Lipídicos/análise , Peróxidos Lipídicos/sangue , Masculino , Úlcera Péptica/metabolismo , Ratos
20.
Cell Tissue Res ; 306(3): 391-8, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11735039

RESUMO

Investigation of the cannabinoid system in a vertebrate group phylogenetically distant from mammals might improve understanding of its physiological role. Thus, in the present study, the distribution of the cannabinoid CB1 receptor has been investigated in the brain of Xenopus laevis (anuran amphibians) by immunohistochemistry, using both light and confocal laser-scanning microscopy. Immunostained neuronal perikarya and terminals were found in the olfactory bulb, dorsal and medial pallium, striatum, and amygdala. Varicosities and nerve terminals containing CB1-like immunoreactivity were also seen in the thalamus and hypothalamus. A number of stained cells were observed in the pars distalis of the pituitary gland. Positive nerve fibers were distributed throughout mesencephalic tegmentum, and in the cerebellum immunolabeling was observed in some Purkinje and possibly Golgi cells. The confocal microscopic analysis of CB1-like and glutamic acid decarboxylase-like immunoreactivities in both the medial pallium of the telencephalon and the olfactory bulbs showed a wide codistribution of the two markers. The present results indicate that distribution of CB1 is conserved in the course of phylogeny. Furthermore, the close relationship between CB1-like and glutamic acid decarboxylase-like immunolabelings point toward the existence of a functional link between cannabinergic and GABAergic innervations also in amphibian brain.


Assuntos
Glutamato Descarboxilase/análise , Bulbo Olfatório/química , Bulbo Olfatório/enzimologia , Receptores de Droga/análise , Animais , Anticorpos , Diencéfalo/química , Evolução Molecular , Feminino , Imunofluorescência , Glutamato Descarboxilase/imunologia , Masculino , Microscopia Confocal , Receptores de Canabinoides , Receptores de Droga/imunologia , Rombencéfalo/química , Telencéfalo/química , Xenopus laevis
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