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1.
Eur Stroke J ; : 23969873241263201, 2024 Jun 25.
Artículo en Inglés | MEDLINE | ID: mdl-38915244

RESUMEN

INTRODUCTION: This study aimed to describe and analyze the rate of clot migration of vessel thrombosis to distal segments in patients with acute ischemic stroke (AIS) who received intravenous thrombolysis (IVT) with tenecteplase (TNK) and alteplase (ALT) before mechanical thrombectomy (MT). In addition, we aimed to determine the relationship between thrombus migration and functional prognosis. METHODS: This study followed the STROBE reporting guidelines. We performed a retrospective analysis of a series of patients from November 2017 to April 2023 with an AIS with thrombosis on CT imaging, treated with IVT (TNK or ALT, split into two distinct groups) prior to mechanical thrombectomy. RESULTS: Two hundred and fifty-six patients with large vessel occlusion (LVO) were included. Ninety-six had received TNK. One hundred and sixty had received ALT. Of the 96 TNK patients, 25 experienced either complete recanalization (n = 3) or thrombus migration (n = 22). Of the 160 ALT patients, 20 experienced either complete recanalization (n = 6) or thrombus migration (n = 14). The difference being statistically substantial for the thrombus migration rate (OR = 3.61, 95% confidence interval: 1.63; 7.98). Migration to an irretrievable very distal segment occurred in four (4%) patients with TNK and in three patients (2%) with ALT (p > 0.05). Thrombus migration was not significantly associated to a different functional prognosis, measured through Rankin scale after 3 months (OR = 0.44, 95% confidence interval: 0.17; 1.12). CONCLUSION: The use of TNK over ALT as a fibrinolytic agent is associated with a higher thrombus migration rate. The migration of thrombi to distal segments, which are theoretically less accessible for mechanical thrombectomy, did not result in worse clinical outcomes.

2.
Eur Stroke J ; : 23969873241241885, 2024 Apr 04.
Artículo en Inglés | MEDLINE | ID: mdl-38572798

RESUMEN

INTRODUCTION: Previous reports and meta-analyses derived from small case series reported a mortality rate of up to 40% in patients with coronavirus disease 2019 associated cerebral venous thrombosis (COVID-CVT). We assessed the clinical characteristics and outcomes in an international cohort of patients with COVID-CVT. PATIENTS AND METHODS: This was a registry study of consecutive COVID-CVT patients diagnosed between March 2020 and March 2023. Data collected by the International Cerebral Venous Thrombosis Consortium from patients with CVT diagnosed between 2017 and 2018 served as a comparison. Outcome analyses were adjusted for age and sex. RESULTS: We included 70 patients with COVID-CVT from 23 hospitals in 15 countries and 206 controls from 14 hospitals in 13 countries. The proportion of women was smaller in the COVID-CVT group (50% vs 68%, p < 0.01). A higher proportion of COVID-CVT patients presented with altered mental state (44% vs 25%, p < 0.01), the median thrombus load was higher in COVID-CVT patients (3 [IQR 2-4] vs 2 [1-3], p < 0.01) and the length of hospital stay was longer compared to controls (11 days [IQR 7-20] vs 8 [4-15], p = 0.02). In-hospital mortality did not differ (5/67 [7%, 95% CI 3-16] vs 7/206 [3%, 2-7], aOR 2.6 [95% CI 0.7-9]), nor did the frequency of functional independence after 6 months (modified Rankin Scale 0-2; 45/58 [78%, 95% CI 65-86] vs 161/185 [87%, 81-91], aOR 0.5 [95% CI 0.2-1.02]). CONCLUSION: In contrast to previous studies, the in-hospital mortality rate and functional outcomes during follow-up did not differ between COVID-CVT patients and the pre-COVID-19 controls.

3.
Int J Mol Sci ; 24(17)2023 Aug 30.
Artículo en Inglés | MEDLINE | ID: mdl-37686257

RESUMEN

We aimed to analyse whether patients with ischaemic stroke (IS) occurring within eight days after the onset of COVID-19 (IS-COV) are associated with a specific aetiology of IS. We used SUPERGNOVA to identify genome regions that correlate between the IS-COV cohort (73 IS-COV cases vs. 701 population controls) and different aetiological subtypes. Polygenic risk scores (PRSs) for each subtype were generated and tested in the IS-COV cohort using PRSice-2 and PLINK to find genetic associations. Both analyses used the IS-COV cohort and GWAS from MEGASTROKE (67,162 stroke patients vs. 454,450 population controls), GIGASTROKE (110,182 vs. 1,503,898), and the NINDS Stroke Genetics Network (16,851 vs. 32,473). Three genomic regions were associated (p-value < 0.05) with large artery atherosclerosis (LAA) and cardioembolic stroke (CES). We found four loci targeting the genes PITX2 (rs10033464, IS-COV beta = 0.04, p-value = 2.3 × 10-2, se = 0.02), previously associated with CES, HS6ST1 (rs4662630, IS-COV beta = -0.04, p-value = 1.3 × 10-3, se = 0.01), TMEM132E (rs12941838 IS-COV beta = 0.05, p-value = 3.6 × 10-4, se = 0.01), and RFFL (rs797989 IS-COV beta = 0.03, p-value = 1.0 × 10-2, se = 0.01). A statistically significant PRS was observed for LAA. Our results suggest that IS-COV cases are genetically similar to LAA and CES subtypes. Larger cohorts are needed to assess if the genetic factors in IS-COV cases are shared with the general population or specific to viral infection.


Asunto(s)
Aterosclerosis , Isquemia Encefálica , COVID-19 , Accidente Cerebrovascular Embólico , Accidente Cerebrovascular Isquémico , Accidente Cerebrovascular , Humanos , Accidente Cerebrovascular/complicaciones , Accidente Cerebrovascular/genética , Isquemia Encefálica/complicaciones , Isquemia Encefálica/genética , COVID-19/complicaciones , COVID-19/genética , Accidente Cerebrovascular Isquémico/genética , Arterias
5.
J Pers Med ; 11(12)2021 Dec 07.
Artículo en Inglés | MEDLINE | ID: mdl-34945790

RESUMEN

Emerging studies have suggested several chromosomal regions as potential host genetic factors involved in the susceptibility to SARS-CoV-2 infection and disease outcome. We nested a COVID-19 genome-wide association study using the GR@ACE/DEGESCO study, searching for susceptibility factors associated with COVID-19 disease. To this end, we compared 221 COVID-19 confirmed cases with 17,035 individuals in whom the COVID-19 disease status was unknown. Then, we performed a meta-analysis with the publicly available data from the COVID-19 Host Genetics Initiative. Because the APOE locus has been suggested as a potential modifier of COVID-19 disease, we added sensitivity analyses stratifying by dementia status or by disease severity. We confirmed the existence of the 3p21.31 region (LZTFL1, SLC6A20) implicated in the susceptibility to SARS-CoV-2 infection and TYK2 gene might be involved in COVID-19 severity. Nevertheless, no statistically significant association was observed in the COVID-19 fatal outcome or in the stratified analyses (dementia-only and non-dementia strata) for the APOE locus not supporting its involvement in SARS-CoV-2 pathobiology or COVID-19 prognosis.

6.
Eur J Neurol ; 28(12): 4078-4089, 2021 12.
Artículo en Inglés | MEDLINE | ID: mdl-34528353

RESUMEN

BACKGROUND AND PURPOSE: The experience gained during the first COVID-19 wave could have mitigated the negative impact on stroke care in the following waves. Our aims were to analyze the characteristics and outcomes of patients with stroke admitted during the second COVID-19 wave and to evaluate the differences in the stroke care provision compared with the first wave. METHODS: This retrospective multicenter cohort study included consecutive stroke patients admitted to any of the seven hospitals with stroke units (SUs) and endovascular treatment facilities in the Madrid Health Region. The characteristics of the stroke patients with or without a COVID-19 diagnosis were compared and the organizational changes in stroke care between the first wave (25 February to 25 April 2020) and second wave (21 July to 21 November 2020) were analyzed. RESULTS: A total of 550 and 1191 stroke patients were admitted during the first and second COVID-19 waves, respectively, with an average daily admission rate of nine patients in both waves. During the second wave, there was a decrease in stroke severity (median National Institutes of Health Stroke Scale 5 vs. 6; p = 0.000), in-hospital strokes (3% vs. 8.1%) and in-hospital mortality (9.9% vs. 15.9%). Furthermore, fewer patients experienced concurrent COVID-19 (6.8% vs. 19.1%), and they presented milder COVID-19 and less severe strokes. Fewer hospitals reported a reduction in the number of SU beds or deployment of SU personnel to COVID-19 dedicated wards during the second wave. CONCLUSIONS: During the second COVID-19 wave, fewer stroke patients were diagnosed with COVID-19, and they had less stroke severity and milder COVID-19.


Asunto(s)
COVID-19 , Accidente Cerebrovascular , Prueba de COVID-19 , Estudios de Cohortes , Humanos , Estudios Retrospectivos , SARS-CoV-2 , Accidente Cerebrovascular/epidemiología
7.
Nat Commun ; 12(1): 3417, 2021 06 07.
Artículo en Inglés | MEDLINE | ID: mdl-34099642

RESUMEN

Genetic discoveries of Alzheimer's disease are the drivers of our understanding, and together with polygenetic risk stratification can contribute towards planning of feasible and efficient preventive and curative clinical trials. We first perform a large genetic association study by merging all available case-control datasets and by-proxy study results (discovery n = 409,435 and validation size n = 58,190). Here, we add six variants associated with Alzheimer's disease risk (near APP, CHRNE, PRKD3/NDUFAF7, PLCG2 and two exonic variants in the SHARPIN gene). Assessment of the polygenic risk score and stratifying by APOE reveal a 4 to 5.5 years difference in median age at onset of Alzheimer's disease patients in APOE ɛ4 carriers. Because of this study, the underlying mechanisms of APP can be studied to refine the amyloid cascade and the polygenic risk score provides a tool to select individuals at high risk of Alzheimer's disease.


Asunto(s)
Enfermedad de Alzheimer/genética , Herencia Multifactorial , Edad de Inicio , Anciano , Anciano de 80 o más Años , Enfermedad de Alzheimer/epidemiología , Enfermedad de Alzheimer/patología , Precursor de Proteína beta-Amiloide/genética , Precursor de Proteína beta-Amiloide/metabolismo , Apolipoproteínas E/genética , Estudios de Casos y Controles , Estudios de Cohortes , Conjuntos de Datos como Asunto , Femenino , Estudios de Seguimiento , Predisposición Genética a la Enfermedad , Estudio de Asociación del Genoma Completo , Heterocigoto , Humanos , Masculino , Persona de Mediana Edad , Polimorfismo de Nucleótido Simple , Medición de Riesgo/métodos , Factores de Riesgo
8.
Stroke ; 52(2): 552-562, 2021 01.
Artículo en Inglés | MEDLINE | ID: mdl-33406872

RESUMEN

BACKGROUND AND PURPOSE: The coronavirus disease 2019 (COVID-19) outbreak has added challenges to providing quality acute stroke care due to the reallocation of stroke resources to COVID-19. Case series suggest that patients with COVID-19 have more severe strokes; however, no large series have compared stroke outcomes with contemporary non-COVID-19 patients. Purpose was to analyze the impact of COVID-19 pandemic in stroke care and to evaluate stroke outcomes according to the diagnosis of COVID-19. METHODS: Retrospective multicenter cohort study including consecutive acute stroke patients admitted to 7 stroke centers from February 25 to April 25, 2020 (first 2 months of the COVID-19 outbreak in Madrid). The quality of stroke care was measured by the number of admissions, recanalization treatments, and time metrics. The primary outcome was death or dependence at discharge. RESULTS: A total of 550 acute stroke patients were admitted. A significant reduction in the number of admissions and secondary interhospital transfers was found. COVID-19 was confirmed in 105 (19.1%) patients, and a further 19 patients were managed as suspected COVID-19 (3.5%). No differences were found in the rates of reperfusion therapies in ischemic strokes (45.5% non-COVID-19, 35.7% confirmed COVID-19, and 40% suspected COVID-19; P=0.265). However, the COVID-19 group had longer median door-to-puncture time (110 versus 80 minutes), which was associated with the performance of chest computed tomography. Multivariate analysis confirmed poorer outcomes for confirmed or suspected COVID-19 (adjusted odds ratios, 2.05 [95% CI, 1.12-3.76] and 3.56 [95% CI, 1.15-11.05], respectively). CONCLUSIONS: This study confirms that patients with COVID-19 have more severe strokes and poorer outcomes despite similar acute management. A well-established stroke care network helps to diminish the impact of such an outbreak in stroke care, reducing secondary transfers and allowing maintenance of reperfusion therapies, with a minor impact on door-to-puncture times, which were longer in patients who underwent chest computed tomography.


Asunto(s)
COVID-19/epidemiología , Brotes de Enfermedades/prevención & control , SARS-CoV-2/patogenicidad , Accidente Cerebrovascular/epidemiología , Accidente Cerebrovascular/virología , Anciano , Anciano de 80 o más Años , COVID-19/complicaciones , Femenino , Hospitalización/estadística & datos numéricos , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos
9.
J Stroke Cerebrovasc Dis ; 30(3): 105570, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33387891

RESUMEN

INTRODUCTION: In previous studies the risk of stroke recurrence has been associated with the left atrial appendage (LAA) morphology (non-chicken wing (NCW)), knowing those with a greater risk as malignant LAA. Recently, a simpler morphological classification has been suggested with two categories: Low-risk (LAA-L) and High-risk (LAA-H); which could be easier to apply and may correlate better with the risk of embolic stroke. METHODS: Retrospective analysis from a registry of patients with recurrent cardioembolic strokes despite appropriate anticoagulant therapy, in which LAA morphology was studied with cardiac CT scan. LAA morphology was classified according to the four current categories and H-L morphology by the same cardiologist. Other variables associated with a high risk of stroke were also assessed, such as CHA2DS2-VASc score and left atrial (LA) size. RESULTS: Twenty-six cases were included in the analysis. We identified 22 (84.6%) chicken wing (CW), 1 (3.8%) windsock and 3 (11.5%) cactus by the current classification system, while 15 (57.7%) were classified as LAA-H and 11 (42.3%) as LAA-L by the new system. Half of the 22 cases with CW morphology were considered LAA-H, whereas all NCW were also classified as LAA-H. LA diameter and area were significantly higher in cases with LAA-H morphology (p=0.03 and 0.014), and also in those CW and LAA-H, compared to those CW with LAA-L (p=0.035). CONCLUSIONS: With this new classification system more than half of the cases of our malignant LAAs were classified as high-risk morphology. This morphology was also associated with an increased LA size.


Asunto(s)
Apéndice Atrial/diagnóstico por imagen , Accidente Cerebrovascular Embólico/etiología , Cardiopatías/diagnóstico por imagen , Tomografía Computarizada por Rayos X , Anciano , Anciano de 80 o más Años , Accidente Cerebrovascular Embólico/diagnóstico por imagen , Femenino , Cardiopatías/complicaciones , Humanos , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Sistema de Registros , Estudios Retrospectivos , Medición de Riesgo , Factores de Riesgo , Terminología como Asunto
10.
Cerebrovasc Dis Extra ; 10(3): 166-173, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33176324

RESUMEN

BACKGROUND: The use of the cardiovascular polypill, a fixed-dose combination treatment, is conceived to improve adherence. However, randomized controlled trials (RCTs) may overestimate it. Studies focusing on cerebrovascular disease and real-life efficacy compared with conventional treatment are lacking. METHODS: This is a retrospective, hospital-based cohort study of acute ischaemic stroke patients who were prescribed a polypill (aspirin 100 mg, atorvastatin 20/40 mg, ramipril 2.5/5/10 mg) versus conventional treatment (aspirin 100 mg and other blood pressure/lipid-lowering agents) in secondary prevention (2017-2018). Clinical records were reviewed 90 days after discharge for stroke recurrence, vascular risk factor control, and safety. Adherence was assessed using the adapted Morisky-Green scale. RESULTS: A total of 104 patients were included (61% male; mean age 69.7 ± 13.9 years); 54 were treated with the polypill and 50 with conventional treatment. No baseline differences in clinical or demographic variables were detected. No recurrences were registered in the polypill group, compared to 1 recurrence in the conventional treatment group. A significant reduction of systolic blood pressure (SBP) was achieved in the polypill group (12.1 mm Hg) compared to the conventional treatment group (6.8 mm Hg) (p = 0.002). No significant differences were detected regarding the goal of LDL cholesterol ≤70 mg/dL (41 vs. 44%). The adverse events were mild and their frequency was similar in the two groups (9 vs. 2%, ns). Adherence was similarly good in the two groups (93 vs. 88%, ns). Polypill group adherence was similar to that reported in a previous meta-analysis of RCTs (93 vs. 84%, ns). CONCLUSION: In our experience, the cardiovascular polypill achieved a higher reduction in SBP levels and was well tolerated. Adherence was similar to that found in the previous literature, which is remarkable given the real-life setting of our study.


Asunto(s)
Inhibidores de la Enzima Convertidora de Angiotensina/administración & dosificación , Aspirina/administración & dosificación , Atorvastatina/administración & dosificación , Trastornos Cerebrovasculares/prevención & control , Inhibidores de Hidroximetilglutaril-CoA Reductasas/administración & dosificación , Inhibidores de Agregación Plaquetaria/administración & dosificación , Ramipril/administración & dosificación , Prevención Secundaria , Administración Oral , Anciano , Anciano de 80 o más Años , Inhibidores de la Enzima Convertidora de Angiotensina/efectos adversos , Aspirina/efectos adversos , Atorvastatina/efectos adversos , Trastornos Cerebrovasculares/diagnóstico , Combinación de Medicamentos , Femenino , Humanos , Inhibidores de Hidroximetilglutaril-CoA Reductasas/efectos adversos , Masculino , Cumplimiento de la Medicación , Persona de Mediana Edad , Inhibidores de Agregación Plaquetaria/efectos adversos , Ramipril/efectos adversos , Recurrencia , Estudios Retrospectivos , Comprimidos , Centros de Atención Terciaria , Factores de Tiempo , Resultado del Tratamiento
11.
Stroke ; 51(9): e254-e258, 2020 09.
Artículo en Inglés | MEDLINE | ID: mdl-32787707

RESUMEN

Recent case-series of small size implied a pathophysiological association between coronavirus disease 2019 (COVID-19) and severe large-vessel acute ischemic stroke. Given that severe strokes are typically associated with poor prognosis and can be very efficiently treated with recanalization techniques, confirmation of this putative association is urgently warranted in a large representative patient cohort to alert stroke clinicians, and inform pre- and in-hospital acute stroke patient pathways. We pooled all consecutive patients hospitalized with laboratory-confirmed COVID-19 and acute ischemic stroke in 28 sites from 16 countries. To assess whether stroke severity and outcomes (assessed at discharge or at the latest assessment for those patients still hospitalized) in patients with acute ischemic stroke are different between patients with COVID-19 and non-COVID-19, we performed 1:1 propensity score matching analyses of our COVID-19 patients with non-COVID-19 patients registered in the Acute Stroke Registry and Analysis of Lausanne Registry between 2003 and 2019. Between January 27, 2020, and May 19, 2020, 174 patients (median age 71.2 years; 37.9% females) with COVID-19 and acute ischemic stroke were hospitalized (median of 12 patients per site). The median National Institutes of Health Stroke Scale was 10 (interquartile range [IQR], 4-18). In the 1:1 matched sample of 336 patients with COVID-19 and non-COVID-19, the median National Institutes of Health Stroke Scale was higher in patients with COVID-19 (10 [IQR, 4-18] versus 6 [IQR, 3-14]), P=0.03; (odds ratio, 1.69 [95% CI, 1.08-2.65] for higher National Institutes of Health Stroke Scale score). There were 48 (27.6%) deaths, of which 22 were attributed to COVID-19 and 26 to stroke. Among 96 survivors with available information about disability status, 49 (51%) had severe disability at discharge. In the propensity score-matched population (n=330), patients with COVID-19 had higher risk for severe disability (median mRS 4 [IQR, 2-6] versus 2 [IQR, 1-4], P<0.001) and death (odds ratio, 4.3 [95% CI, 2.22-8.30]) compared with patients without COVID-19. Our findings suggest that COVID-19 associated ischemic strokes are more severe with worse functional outcome and higher mortality than non-COVID-19 ischemic strokes.


Asunto(s)
Isquemia Encefálica/complicaciones , Infecciones por Coronavirus/complicaciones , Neumonía Viral/complicaciones , Accidente Cerebrovascular/complicaciones , Anciano , Anciano de 80 o más Años , Isquemia Encefálica/diagnóstico por imagen , Isquemia Encefálica/terapia , COVID-19 , Estudios de Cohortes , Infecciones por Coronavirus/diagnóstico por imagen , Infecciones por Coronavirus/terapia , Evaluación de la Discapacidad , Femenino , Humanos , Masculino , Persona de Mediana Edad , Pandemias , Neumonía Viral/diagnóstico por imagen , Neumonía Viral/terapia , Puntaje de Propensión , Recuperación de la Función , Sistema de Registros , Accidente Cerebrovascular/diagnóstico por imagen , Accidente Cerebrovascular/terapia , Análisis de Supervivencia , Tiempo de Tratamiento , Tomografía Computarizada por Rayos X , Resultado del Tratamiento
14.
Neurologist ; 24(1): 33-36, 2019 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-30586033

RESUMEN

INTRODUCTION: Castleman disease (CD) is a rare pathologic process of unknown etiology, characterized by non-neoplastic lymph node enlargement. Two distinct histologic patterns are recognized; the hyaline-vascular type and the less common plasma cells type. Another intermediate type has been described. The clinical features are classified into 2 categories, localized (unicentric) and generalized (multicentric), the later associated with systemic manifestations and poor prognosis. CD affecting the central nervous system is extremely rare. We report a new case of localized intracranial CD and we accomplish a review of the literature. CASE REPORT: A 30-year-old man presented with a generalized tonic-clonic seizure. Computerized tomography and magnetic resonance imaging showed a small mass in the right temporoparietal convexity with homogenous enhancement after contrast administration. Extensive vasogenic edema in comparison with the size of the mass was also identified and based on the neuroradiologic finding, a suspected diagnosis of meningoangiomatosis was formulated. The mass was completely resected and his histologic examination identified the hyaline-vascular type of CD. One year after surgery, the patient remains seizure free, without evidence of systemic involvement or recurrence of the mass. CONCLUSIONS: Our case and review of the literature show the value of the extensive brain edema on neuroimaging finding to the differential diagnosis for a solitary mass arising from the meninges. We emphasize on the need for histologic examination when the diagnosis of meningioma is not entirely clear.


Asunto(s)
Encéfalo/diagnóstico por imagen , Encéfalo/patología , Enfermedad de Castleman/diagnóstico por imagen , Enfermedad de Castleman/patología , Convulsiones/etiología , Adulto , Edema Encefálico/etiología , Enfermedad de Castleman/complicaciones , Enfermedad de Castleman/cirugía , Humanos , Imagen por Resonancia Magnética , Masculino , Tomografía Computarizada por Rayos X
15.
Toxins (Basel) ; 10(6)2018 05 28.
Artículo en Inglés | MEDLINE | ID: mdl-29843420

RESUMEN

Botulinum toxin type A is one of the most useful treatments of sialorrhea in neurological disorders. Evidence for the use of incobotulinumtoxin A (inco-A) in the treatment of sialorrhea is limited. Thirty-six patients with sialorrhea were treated with infiltrations of inco-A into both parotid glands. The severity of sialorrhea was evaluated by the Drooling Severity Scale (DSS), and the Drooling Frequency Scale (DFS). Patients' perceptions of clinical benefit were recorded via the Patient Global Impression of Improvement (PGI-I) scale. Following treatment, there was a significant difference in both the DFS and the DSS (p < 0.001). Clinical benefits on the basis of the PGI-I were present in up to 90% of patients.


Asunto(s)
Toxinas Botulínicas Tipo A/uso terapéutico , Enfermedades del Sistema Nervioso/tratamiento farmacológico , Fármacos Neuromusculares/uso terapéutico , Neurotoxinas/uso terapéutico , Sialorrea/tratamiento farmacológico , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad , Glándula Parótida , Resultado del Tratamiento
16.
Front Neuroanat ; 10: 83, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27616982

RESUMEN

T-type calcium (Ca(2+)) channels play a central role in regulating membrane excitability in the brain. Although the contributions of T-type current to neuron output is often proposed to reflect a differential distribution of T-type channel subtypes to somato-dendritic compartments, their precise subcellular distributions in central neurons are not fully determined. Using histoblot and high-resolution immunoelectron microscopic techniques, we have investigated the expression, regional distribution and subcellular localization of T-type Cav3.1 and Cav3.2 channel subunits in the adult brain, as well as the ontogeny of expression during postnatal development. Histoblot analysis showed that Cav3.1 and Cav3.2 proteins were widely expressed in the brain, with mostly non-overlapping patterns. Cav3.1 showed the highest expression level in the molecular layer (ml) of the cerebellum (Cb), and Cav3.2 in the hippocampus (Hp) and the ml of Cb. During development, levels of Cav3.1 and Cav3.2 increased with age, although there were marked region- and developmental stage-specific differences in their expression. At the cellular and subcellular level, immunoelectron microscopy showed that labeling for Cav3.1 was present in somato-dendritic domains of hippocampal interneurons and Purkinje cells (PCs), while Cav3.2 was present in somato-dendritic domains of CA1 pyramidal cells, hippocampal interneurons and PCs. Most of the immunoparticles for Cav3.1 and Cav3.2 were either associated with the plasma membrane or the intracellular membranes, with notable differences depending on the compartment. Thus, Cav3.1 was mainly located in the plasma membrane of interneurons, whereas Cav3.2 was mainly located in the plasma membrane of dendritic spines and had a major intracellular distribution in dendritic shafts. In PCs, Cav3.1 and Cav3.2 showed similar distribution patterns. In addition to its main postsynaptic distribution, Cav3.2 but not Cav3.1 was also detected in axon terminals establishing excitatory synapses. These results shed new light on the subcellular localization of T-type channel subunits and provide evidence for the non-uniform distribution of Cav3.1 and Cav3.2 subunits over the plasma membrane of central neurons, which may account for the functional heterogeneity of T-type mediated current.

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