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1.
Neurologia (Engl Ed) ; 39(2): 190-195, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37442427

RESUMEN

INTRODUCTION: Visual snow syndrome (VSS) is a central nervous system disorder that consists of the constant perception of small black and white dots throughout the entire visual field. DEVELOPMENT: VSS can present from infancy to old age, with greater prevalence in the young population, and shows no difference between sexes. The diagnostic criteria include the presence of visual snow and such other visual phenomena as palinopsia, photophobia, nyctalopia, and other persistent visual phenomena. The pathophysiology of VSS is unknown, but hyperexcitability of the visual cortex and a dysfunction in higher-order visual processing are postulated as potential mechanisms. The prevalence of migraine among patients with VSS is high, compared to the general population, and symptoms are more severe in patients presenting both conditions. No effective treatment is available, but the drug with the best results is lamotrigine, which is recommended only in selected cases with severe functional limitation. CONCLUSIONS: VSS is a little-known and underdiagnosed entity, but the increasing number of studies in recent years has made it possible to establish diagnostic criteria and begin studying its pathophysiology. This entity is closely related to migraine, with overlapping symptoms and probably shared pathophysiological mechanisms.


Asunto(s)
Trastornos Migrañosos , Migraña con Aura , Trastornos de la Percepción , Humanos , Migraña con Aura/diagnóstico , Migraña con Aura/epidemiología , Trastornos de la Visión/etiología , Trastornos Migrañosos/epidemiología , Trastornos Migrañosos/diagnóstico
2.
AJNR Am J Neuroradiol ; 43(9): 1304-1310, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-35981762

RESUMEN

BACKGROUND AND PURPOSE: The treatment of symptomatic carotid near-occlusion is controversial. Our aim was to analyze the results of carotid endarterectomy and carotid artery stent placement in patients with symptomatic carotid near-occlusion and to identify factors related to technical failure, periprocedural complications, and restenosis. MATERIALS AND METHODS: We conducted a multicenter, prospective nonrandomized study. Patients with angiography-confirmed carotid near-occlusion were included. We assessed the revascularization rate and periprocedural stroke or death. Twenty-four-month clinical and carotid imaging follow-up was performed, and rates of carotid restenosis or occlusion, ipsilateral stroke, and mortality were analyzed. Carotid artery stent placement, carotid endarterectomy, and medical treatment were compared. RESULTS: One hundred forty-one patients were included. Forty-four carotid artery stent placement and 23 carotid endarterectomy procedures were performed within 6 months after the event. Complete revascularization was achieved in 83.6%, 81.8% in the carotid artery stent placement group and 87% with carotid endarterectomy (P = .360). Periprocedural stroke or death occurred in 6% (carotid artery stent placement = 2.3%; carotid endarterectomy = 13%; P = .077) and was not related to revascularization failure. The carotid restenosis or occlusion rate was 8.3% (5% restenosis, 3.3% occlusion); with carotid artery stent placement it was 10.5%; and with carotid endarterectomy it was 4.5% (P = .419). The 24-month cumulative rate of ipsilateral stroke was 4.8% in the carotid artery stent placement group, 17.4% for carotid endarterectomy, and 13.1% for medical treatment (P = .223). Mortality was 12%, 4.5%, and 5.6%, respectively (P = .422). Revascularization failure and restenosis occurred more frequently in patients with full collapse compared with patients without full collapse (33.3% versus 5.6%, P = .009; 21.4% versus 2.9%, P = .032, respectively). CONCLUSIONS: Carotid artery stent placement and carotid endarterectomy are associated with high rates of failure and periprocedural stroke. Carotid near-occlusion with full collapse appears to be associated with an increased risk of technical failure and restenosis. Carotid near-occlusion revascularization does not seem to reduce the risk of stroke at follow-up compared with medical treatment.


Asunto(s)
Enfermedades de las Arterias Carótidas , Estenosis Carotídea , Endarterectomía Carotidea , Accidente Cerebrovascular , Humanos , Estenosis Carotídea/diagnóstico por imagen , Estenosis Carotídea/cirugía , Estenosis Carotídea/complicaciones , Estudios Prospectivos , Endarterectomía Carotidea/efectos adversos , Accidente Cerebrovascular/complicaciones , Enfermedades de las Arterias Carótidas/complicaciones , Stents/efectos adversos , Sistema de Registros , Resultado del Tratamiento , Factores de Riesgo
3.
Neurologia (Engl Ed) ; 2021 Sep 11.
Artículo en Inglés, Español | MEDLINE | ID: mdl-34521544

RESUMEN

INTRODUCTION: Visual snow syndrome (VSS) is a central nervous system disorder that consists of the constant perception of small black and white dots throughout the entire visual field. DEVELOPMENT: VSS can present from infancy to old age, with greater prevalence in the young population, and shows no difference between sexes. The diagnostic criteria include the presence of visual snow and such other visual phenomena as palinopsia, photophobia, nyctalopia, and other persistent visual phenomena. The pathophysiology of VSS is unknown, but hyperexcitability of the visual cortex and a dysfunction in higher-order visual processing are postulated as potential mechanisms. The prevalence of migraine among patients with VSS is high, compared to the general population, and symptoms are more severe in patients presenting both conditions. No effective treatment is available, but the drug with the best results is lamotrigine, which is recommended only in selected cases with severe functional limitation. CONCLUSIONS: VSS is a little-known and underdiagnosed entity, but the increasing number of studies in recent years has made it possible to establish diagnostic criteria and begin studying its pathophysiology. This entity is closely related to migraine, with overlapping symptoms and probably shared pathophysiological mechanisms.

4.
Neuroradiology ; 63(5): 705-711, 2021 May.
Artículo en Inglés | MEDLINE | ID: mdl-33025041

RESUMEN

PURPOSE: The ultrasonographic and hemodynamic features of patients with carotid near-occlusion (CNO) are still not well known. Our aim was to describe the ultrasonographic and hemodynamic characteristics of a cohort of patients with CNO. METHODS: A prospective, observational, nationwide, and multicenter study was conducted from January/2010 to May/2016. Patients with digital subtraction angiography (DSA)-confirmed CNO were included. We collected information on clinical and demographic characteristics, carotid and transcranial ultrasonography and DSA findings, presence of full-collapse, collateral circulation, and cerebrovascular reactivity (CVR). RESULTS: One hundred thirty-five patients were analyzed. Ultrasonographic and DSA diagnosis of CNO were concordant in only 44%. This disagreement was related to the presence/absence of full-collapse: 45% of patients with CNO with full-collapse were classified as a complete carotid occlusion, and 40% with a CNO without full-collapse were interpreted as severe stenosis (p < 0.001). Mean velocities (mV) and pulsatility indexes (PIs) were significantly lower in the ipsilateral middle cerebral artery compared with the contralateral (43 cm/s vs 58 cm/s, p < 0.001; 0.80 vs 1.00, p < 0.001). Collateral circulation was identified in 92% of patients, with the anterior communicating artery (73%) being the most frequent. CVR was decreased or exhausted in 66% of cases and was more frequent in patients with a poor or absent collateral network compared with patients with ≥ 2 collateral arteries (82% vs 56%, p = 0.051). CONCLUSION: The accuracy of carotid ultrasonography in the diagnosis of CNO seems to be limited, with significant discrepancies with DSA. Decreased ipsilateral mV, PI, and CVR suggest a hemodynamic compromise in patients with CNO.


Asunto(s)
Enfermedades de las Arterias Carótidas , Estenosis Carotídea , Arteria Carótida Interna/diagnóstico por imagen , Estenosis Carotídea/diagnóstico por imagen , Circulación Cerebrovascular , Circulación Colateral , Hemodinámica , Humanos , Estudios Prospectivos , Sistema de Registros , Ultrasonografía Doppler Transcraneal
5.
Eur J Neurol ; 26(11): 1391-1398, 2019 11.
Artículo en Inglés | MEDLINE | ID: mdl-31126001

RESUMEN

BACKGROUND AND PURPOSE: The risk of recurrent stroke amongst patients with symptomatic carotid near-occlusion (SCNO) has not been clearly established, and its management remains controversial. The aim was to define the 24-month risk of recurrent stroke and to analyse the effect of the different treatment modalities (medical treatment and revascularization) in a population of patients with SCNO. METHODS: A multicentre, nationwide, prospective study from January 2010 to May 2016 was performed. Patients with angiography-confirmed SCNO were included. The primary end-point was ipsilateral ischaemic stroke including periprocedural events within 24 months following the presenting event. Revascularization results and periprocedural complications, ipsilateral transient ischaemic attack, disabling or fatal stroke, and mortality were also noted. RESULTS: The study population comprised 141 patients from 17 Spanish centres. Seventy patients (49.6%) were treated by revascularization (carotid stenting in 47, endarterectomy in 23). Complete revascularization was achieved in 58 patients (83%). Periprocedural stroke or death occurred in 5.7%. The 24-month cumulative incidence of the primary end-point was 11.1% (95% confidence interval 5.8-16.4; n = 15), 12% in the medical treatment group and 10.2% in the revascularization group, log-rank P = 0.817. The cumulative rates of ipsilateral ischaemic stroke or transient ischaemic attack, disabling or fatal stroke, and mortality, were 17%, 4.5% and 7.5%, respectively. CONCLUSIONS: The rate of ipsilateral ischaemic stroke in patients with SCNO seems to be lower than the known rate associated with severe carotid stenosis without near-occlusion. The potential benefit of revascularization in the prevention of stroke in patients with SCNO may be influenced by the effectiveness and safety of the procedure.


Asunto(s)
Estenosis Carotídea/complicaciones , Estenosis Carotídea/epidemiología , Accidente Cerebrovascular/epidemiología , Accidente Cerebrovascular/etiología , Anciano , Anciano de 80 o más Años , Angiografía de Substracción Digital , Estenosis Carotídea/cirugía , Angiografía Cerebral , Revascularización Cerebral , Endarterectomía Carotidea , Determinación de Punto Final , Femenino , Humanos , Ataque Isquémico Transitorio/etiología , Masculino , Persona de Mediana Edad , Procedimientos Neuroquirúrgicos , Estudios Prospectivos , Sistema de Registros , España/epidemiología , Accidente Cerebrovascular/mortalidad
6.
Case Rep Neurol Med ; 2014: 528268, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25525533

RESUMEN

Although few patients with spontaneous intracranial hypotension develop cerebral venous thrombosis, the association between these two entities seems too common to be simply a coincidental finding. We describe two cases of spontaneous intracranial hypotension associated with cerebral venous thrombosis. In one case, extensive cerebral venous thrombosis involved the superior sagittal sinus and multiple cortical cerebral veins. In the other case, only a right frontoparietal cortical vein was involved. Several mechanisms could contribute to the development of cerebral venous thrombosis in spontaneous intracranial hypotension. When spontaneous intracranial hypotension and cerebral venous thrombosis occur together, it raises difficult practical questions about the treatment of these two conditions. In most reported cases, spontaneous intracranial hypotension was treated conservatively and cerebral venous thrombosis was treated with anticoagulation. However, we advocate aggressive treatment of the underlying cerebrospinal fluid leak.

8.
Rev Med Interne ; 31(6): e7-9, 2010 Jun.
Artículo en Francés | MEDLINE | ID: mdl-20227147

RESUMEN

Hepatocellular carcinoma and other tumours of the liver are extremely rare in Wilson's disease. We report a patient who presented with a cholangiocarcinoma associated with Wilson's disease. The literature review underlines that patients with Wilson's disease should be considered at risk of hepatocellular carcinoma, cholangiocarcinoma and undifferentiated carcinoma in the liver. Risk factors seem to be long disease duration and probably a poor observance to therapy. A liver imaging should be included in the follow-up of patients with Wilson's disease.


Asunto(s)
Neoplasias de los Conductos Biliares/complicaciones , Conductos Biliares Intrahepáticos , Colangiocarcinoma/complicaciones , Degeneración Hepatolenticular/complicaciones , Adulto , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Neoplasias de los Conductos Biliares/diagnóstico , Neoplasias de los Conductos Biliares/tratamiento farmacológico , Colangiocarcinoma/diagnóstico , Colangiocarcinoma/tratamiento farmacológico , Resultado Fatal , Degeneración Hepatolenticular/diagnóstico , Degeneración Hepatolenticular/tratamiento farmacológico , Humanos , Masculino , Factores de Riesgo
9.
Ontogenez ; 40(4): 270-81, 2009.
Artículo en Ruso | MEDLINE | ID: mdl-19705758

RESUMEN

The morphological changes in the development of serotonergic neurons of the dorsal raphe nuclei in the medulla oblongata was studied by immunocytochemistry in mice with knockout of 1A and 1B serotonin autoreceptors as well as monoamine oxidase A. Serotonin autoreceptors regulate electric activity of serotonergic neurons as well as the synthesis and release of the neurotransmitter, while monoamine oxidase A catalyzes its degradation. These genetic modifications proved to have no effect on the number of serotonergic neurons in the medulla oblongata but induced morphofunctional changes. Decreased cell size and increased intracellular serotonin level were observed in the case of monoamine oxidase A deficiency, while excessive cell size and decreased intracellular serotonin level were observed in the case of autoreceptor deficiency. The data obtained confirm the hypothesis of autoregulation of serotonergic neurons in development.


Asunto(s)
Monoaminooxidasa/fisiología , Neuronas/citología , Núcleos del Rafe/citología , Receptor de Serotonina 5-HT1A/fisiología , Receptor de Serotonina 5-HT1B/fisiología , Serotonina/metabolismo , Animales , Animales Recién Nacidos , Autorreceptores/genética , Autorreceptores/fisiología , Tamaño de la Célula , Bulbo Raquídeo/citología , Bulbo Raquídeo/embriología , Bulbo Raquídeo/crecimiento & desarrollo , Bulbo Raquídeo/metabolismo , Ratones , Ratones Noqueados , Monoaminooxidasa/genética , Neuronas/metabolismo , Núcleos del Rafe/embriología , Núcleos del Rafe/crecimiento & desarrollo , Núcleos del Rafe/metabolismo , Receptor de Serotonina 5-HT1A/genética , Receptor de Serotonina 5-HT1B/genética
11.
Gastroenterol Clin Biol ; 32(11): 926-30, 2008 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-18947950

RESUMEN

We report a case of massive pulmonary embolism during cyanoacrylate glue endoscopic injection in a patient with gastric varices from portal hypertension. A review of the literature and results in an animal model show the physiopathology and risk factors associated with this endoscopic procedure.


Asunto(s)
Cianoacrilatos/efectos adversos , Várices Esofágicas y Gástricas/terapia , Embolia Pulmonar/inducido químicamente , Enfermedad Aguda , Cianoacrilatos/administración & dosificación , Resultado Fatal , Humanos , Escleroterapia
12.
Gastroenterol Clin Biol ; 32(1 Pt. 1): 74-8, 2008 Jan.
Artículo en Francés | MEDLINE | ID: mdl-18405652

RESUMEN

Bleeding from a pseudoaneurysm is a rare complication of chronic pancreatitis. We present two cases of ruptured pseudoaneurysms of the hepatic arteries. The first case involved a pancreatic pseudocyst that ruptured in the duodenum and the second resulted in an intrahepatic hematoma that compressed the bile tract causing secondary hemobilia. Angiographic embolization was the primary treatment in both cases, with surgery for the first patient and later radiological drainage in the second. The hemorrhage was controlled in both cases despite the severe prognosis and high mortality in these cases.


Asunto(s)
Aneurisma Falso/etiología , Arteria Hepática/patología , Pancreatitis Crónica/complicaciones , Adulto , Aneurisma Roto/etiología , Úlcera Duodenal/etiología , Embolización Terapéutica , Hematoma/etiología , Hemobilia/etiología , Humanos , Hepatopatías/etiología , Masculino , Persona de Mediana Edad , Seudoquiste Pancreático/complicaciones , Pancreaticoduodenectomía , Úlcera Péptica Hemorrágica/etiología
14.
Rev Neurol ; 45(3): 129-33, 2007.
Artículo en Español | MEDLINE | ID: mdl-17661269

RESUMEN

INTRODUCTION AND AIMS: Until now treatment of acute cerebral infarction with tissue plasminogen activator (rt-PA) has been applied to a limited extent in large medical centres with acute stroke units. The aim of this study is to determine the safety and effectiveness of this treatment in a centre with no previous experience following a multidisciplinary model. PATIENTS AND METHODS: We conducted a prospective, observation-based study involving patients who were treated with intravenous rt-PA within 3 hours of suffering an acute ischaemic stroke between January 2004 and December 2006. Basal variables, haemorrhagic complications, response to treatment and functional progress were evaluated using the modified Rankin Scale (mRS) at 3 months. Treatment and control were applied following a multidisciplinary protocol implemented by the Intensive Medicine and Neurology services. RESULTS: In all, 46 patients were treated, their mean age being 67 +/- 12 years (63% males). NIH pre-treatment: 13.6 +/- 4.7; median: 13.5; range: 5-22. Time elapsed between the onset of symptoms and arrival at the hospital was 53 +/- 27 min, and door-to-needle time was 69 +/- 27 min. At 24 hours, 48% of patients had improved their scores on the NIH scale > 4 points. A total of 10 haemorrhagic transformations (21.7%) were observed, none of which were symptomatic. At three months, 54.3% of patients were functionally independent (mRS: 0-2). Mortality rate at 90 days was 13.1%. CONCLUSIONS: Administration of rt-PA to patients with acute ischaemic stroke in health care practice following a multidisciplinary protocol is safe and has a neurological progression that is comparable to clinical trials and studies.


Asunto(s)
Infarto Cerebral/terapia , Fibrinolíticos/uso terapéutico , Terapia Trombolítica/estadística & datos numéricos , Activador de Tejido Plasminógeno/uso terapéutico , Adulto , Anciano , Anciano de 80 o más Años , Infarto Cerebral/patología , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Estudios Retrospectivos , Análisis de Supervivencia , Factores de Tiempo , Resultado del Tratamiento
15.
Neuroscience ; 138(2): 561-73, 2006.
Artículo en Inglés | MEDLINE | ID: mdl-16364554

RESUMEN

Lumbar spinothalamic neurons in the lamina X of the L3-L4 spinal cord segment have been proposed to constitute the spinal ejaculation generator in male rats. Lumbar spinothalamic cells are immunoreactive for galanin and neurokinin-1 receptors. We previously showed that after injection of pseudorabies virus either in the bulbospongiosus muscle or in the prostate, retrogradely labeled cells in the L3-L4 segment also displayed galanin or neurokinin-1 receptor immunoreactivities, demonstrating a direct link between lumbar spinothalamic cells and two anatomical structures involved in the two phases of ejaculation i.e. the emission and the expulsion phases. In order to provide with a more precise anatomical support for the role of lumbar spinothalamic cells in controlling ejaculation, we injected simultaneously in male adult rats two strains of recombinant pseudorabies virus, expressing either beta-galactosidase (PRV-BaBlu) or green fluorescent protein (PRV-152) in the prostate and in the bulbospongiosus muscle, respectively. After 5 days, we performed multiple immunofluorescence experiments to detect PRV-BaBlu, PRV-152 and galanin or neurokinin-1 receptors in transverse sections of the L1-S1 segment. Double- and triple-labeled cells were counted using confocal laser scanning microscope. Double-labeled neurons with the two strains of pseudorabies virus were mainly found at the L3-L4 segment lateral to the central canal in lamina X and represented about 60% of the total number of pseudorabies virus-labeled neurons. All the double pseudorabies virus-labeled neurons also expressed lumbar spinothalamic and most of them neurokinin-1 receptor, identifying them as lumbar spinothalamic neurons. The convergence of retrograde labeling from prostate and bulbospongiosus muscle on the same lumbar spinothalamic cells strongly reinforce their role in the spinal control and coordination of the emission and expulsion of sperm.


Asunto(s)
Músculo Liso/inervación , Neuronas/fisiología , Próstata/inervación , Médula Espinal/fisiología , Animales , Colina O-Acetiltransferasa/análisis , Eyaculación , Genes Reporteros , Proteínas Fluorescentes Verdes/análisis , Proteínas Fluorescentes Verdes/genética , Herpesvirus Suido 1/genética , Vértebras Lumbares , Masculino , Ratas , Ratas Sprague-Dawley , beta-Galactosidasa/análisis , beta-Galactosidasa/genética
16.
Neuroscience ; 134(4): 1325-41, 2005.
Artículo en Inglés | MEDLINE | ID: mdl-16054769

RESUMEN

Ejaculation requires the coordination of sympathetic, parasympathetic and somatic neural outputs. Timely occurrence of the emission and expulsion of sperm results from an interplay between spinal nuclei innervating the seminal tract and the sexual accessory glands including the prostate on the one hand, and on the other hand perineal striated muscles, particularly the bulbospongiosus muscle. A group of cells essential for ejaculation, located around the central canal and referred to as lumbar spinothalamic neurons have been recently identified. Lumbar spinothalamic neurons are immunoreactive for galanin and neurokinin-1 receptor. In order to investigate the anatomical relationships between lumbar spinothalamic neurons and both the prostate and the bulbospongiosus muscle, pseudorabies virus retrograde tracing technique was used combined with immunohistochemistry. Three to five days after pseudorabies virus injection in the bulbospongiosus muscle or the prostate in male rats, spinal cord sections were processed for double immunofluorescence against pseudorabies virus and galanin or neurokinin-1 receptor. Immunocytochemical experiments against pseudorabies virus and choline acetyltransferase were also performed to discriminate between motoneurons and preganglionic neurons, or interneurons. Spinal sections were examined with confocal laser scanning microscope. Three days after pseudorabies virus injection within the prostate and the bulbospongiosus muscle, sympathetic preganglionic neurons and motoneurons of the dorsomedial nucleus were retrogradely labeled, respectively. Five days after pseudorabies virus injection, transsynaptically labeled choline acetyltransferase-negative neurons were found mainly located in the medial gray surrounding the central canal from L1 to S1. At the L3-L4 level, most of transsynaptically labeled neurons were immunoreactive for galanin and to a lesser extent for neurokinin-1 receptor, strongly suggesting that they could be the lumbar spinothalamic cells. We have thus evidenced connections between these cells and motoneurons of the dorsomedial nucleus and both sympathetic and parasympathetic preganglionic neurons innervating the bulbospongiosus muscle and the prostate, respectively. These anatomical data reinforce the crucial role for lumbar spinothalamic cells in coordinating the spinal control of ejaculation.


Asunto(s)
Eyaculación/fisiología , Neuronas/citología , Próstata/inervación , Receptores de Galanina/metabolismo , Receptores de Neuroquinina-1/metabolismo , Animales , Colina O-Acetiltransferasa/metabolismo , Inmunohistoquímica , Región Lumbosacra , Masculino , Microscopía Confocal , Músculo Esquelético/inervación , Vías Nerviosas/citología , Vías Nerviosas/metabolismo , Neuronas/metabolismo , Ratas , Ratas Sprague-Dawley , Médula Espinal/citología
18.
Eur J Neurosci ; 16(7): 1240-8, 2002 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-12405984

RESUMEN

In the male rat, serotoninergic neurons of the ventrolateral medulla send direct projections onto spinal preganglionic neurons that innervate the penis. The role of the paraventricular nucleus of the hypothalamus in the control of penile erection is well recognized. Our aim was to demonstrate anatomical relation between paraventricular neurons and medullary serotoninergic neurons innervating the penis. In adult male rats, stereotaxic iontophoretic injections of Phaseolus vulgaris leuco-agglutinin were performed in the paraventricular nucleus. Neurons in the ventrolateral medulla were retrogradely labelled using transneuronal retrograde transport of pseudorabies virus injected in the corpus cavernosum. Sections of the ventro-lateral medulla were processed for double immunofluorescence to reveal both Phaseolus vulgaris leuco-agglutinin and pseudorabies virus using specific antibodies. Sections were also processed for the simultaneous detection of pseudorabies virus and serotonin. Pseudorabies virus-infected neurons in the ventrolateral medulla were present in the nucleus paragigantocellularis, reticular formation of the medulla, raphe pallidus and raphe magnus. In the nucleus paragigantocellularis, all pseudorabies virus-infected-neurons were immunoreactive for serotonin. Some of them received Phaseolus vulgaris leuco-agglutinin-labelled varicose fibres that ran along the soma of pseudorabies virus-infected neurons. Confocal microscopy suggested the presence of several close appositions between them, which were demonstrated using three-dimensional reconstruction of serial optical sections. Our results show that paraventricular neurons send direct projections in the nucleus paragigantocellularis onto neurons that innervate the penis. They suggest a possible role of the paraventricular nucleus in penile erection through the control of descending serotoninergic raphe-spinal neurons. The neurotransmitter used in this pathway remains to be determined.


Asunto(s)
Bulbo Raquídeo/anatomía & histología , Núcleo Hipotalámico Paraventricular/anatomía & histología , Erección Peniana/fisiología , Pene/inervación , Animales , Vías Eferentes , Herpesvirus Suido 1 , Imagenología Tridimensional , Inmunohistoquímica , Masculino , Microscopía Confocal , Neuronas/citología , Neuronas/metabolismo , Pene/fisiología , Fitohemaglutininas , Ratas , Ratas Sprague-Dawley , Serotonina/metabolismo , Coloración y Etiquetado
19.
Eur J Neurosci ; 15(3): 449-57, 2002 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-11876772

RESUMEN

Following the cloning and sequencing of the A subunit of the 5-HT3 receptor, two alternatively spliced isoforms, 5-HT3-AS and 5-HT3-AL, have been identified. In order to analyse the distribution of the receptor, a polyclonal antibody has been produced against the short form which is the most abundant in the central nervous system [Doucet et al. (2000) Neuroscience 95, 881-892]. As expected from the recognition of functional 5-HT3 receptors, immunostaining by this anti-5-HT3-R-AS antibody matched the distribution of the high-affinity 5-HT3 binding sites in the rat brain and spinal cord. 5-HT3-AS-like immunoreactivity was detected at low levels in the limbic system, particularly in the amygdala and the hippocampus, and in the frontal, piriform and entorhinal cortices. High levels of immunoreactivity were found in the brainstem, mainly in the nucleus tractus solitarius and the nucleus of the spinal tract of the trigeminal nerve, and in the dorsal horn of the spinal cord. At the ultrastructural level, immunostaining was generally found associated with axons and nerve terminals (70-80%) except in the hippocampus, where labelled dendrites were more abundant (56%). This preferential localization on nerve endings is consistent with the well-documented physiological role of 5-HT3 receptors in the control of neurotransmitter release. However, the different distribution in the hippocampus raises the question of whether differential addressing mechanisms exist for preferentially targeting 5-HT3 receptors to postsynaptic dendritic sites as compared to presynaptic nerve endings, depending on the nature of the neurons bearing these receptors.


Asunto(s)
Compartimento Celular/fisiología , Sistema Nervioso Central/metabolismo , Dendritas/metabolismo , Terminales Presinápticos/metabolismo , Receptores de Serotonina/metabolismo , Transmisión Sináptica/fisiología , Animales , Sistema Nervioso Central/ultraestructura , Dendritas/ultraestructura , Inmunohistoquímica , Masculino , Microscopía Electrónica , Terminales Presinápticos/ultraestructura , Ratas , Ratas Wistar , Receptores de Serotonina 5-HT3 , Serotonina/metabolismo , Membranas Sinápticas/metabolismo , Membranas Sinápticas/ultraestructura
20.
J Chem Neuroanat ; 22(3): 185-203, 2001 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-11522440

RESUMEN

The distributions of 5-hydroxytryptamine (5-HT)-immunoreactive (IR) varicosities and 5-hydroxytryptamine-2A receptor (5-HT2A)-IR neuronal structures in the rat brain have previously been described individually. Using double labeling immunocytochemistry, the relationships between 5-HT2A-IR and 5-HT-IR elements in the forebrain of male rats has been studied at the light microscopic level. In neocortical regions (frontal, parietal and retrosplenial cortex), the strongest 5-HT2A-IR was found in the apical dendrites of pyramidal cells in layers III-V, while 5-HT-IR terminal-like varicosities were present in all layers but most prominently in the outer layers. In other forebrain regions, the olfactory bulb, the hippocampal formation, and the islands of Calleja and Calleja magna, localized discrepancies were present between the 5-HT2A-IR neuronal profiles and the 5-HT-IR terminal-like varicosities. Hardly any additional juxtapositions between the 5-HT2A-IR neuronal profiles and 5-HT-IR terminal-like varicosities were revealed when the intraneuronal level of 5-HT was increased by monoamine oxidase inhibitor pretreatment (nialamide, 250 mg/kg, 3 h). Thus, in most forebrain regions, there were overall few juxtapositions between 5-HT terminal-like varicosities and 5-HT2A-IR neuronal structures. This observation suggests that 5-HT2A receptor mediated 5-HT transmission in the rat forebrain is mainly a volume transmission process mediated via short distance diffusion in the extra-cellular space.


Asunto(s)
Dendritas/metabolismo , Terminales Presinápticos/metabolismo , Prosencéfalo/metabolismo , Receptores de Serotonina/metabolismo , Serotonina/metabolismo , Transmisión Sináptica/fisiología , Animales , Cuerpo Estriado/citología , Cuerpo Estriado/metabolismo , Dendritas/ultraestructura , Hipocampo/citología , Hipocampo/metabolismo , Inmunohistoquímica , Islotes Olfatorios/citología , Islotes Olfatorios/metabolismo , Masculino , Neocórtex/citología , Neocórtex/metabolismo , Bulbo Olfatorio/metabolismo , Bulbo Olfatorio/ultraestructura , Vías Olfatorias/citología , Vías Olfatorias/metabolismo , Terminales Presinápticos/ultraestructura , Prosencéfalo/citología , Células Piramidales/citología , Células Piramidales/metabolismo , Ratas , Ratas Sprague-Dawley , Receptor de Serotonina 5-HT2A
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