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1.
Epilepsia ; 2024 May 23.
Artículo en Inglés | MEDLINE | ID: mdl-38780490

RESUMEN

OBJECTIVE: Sex determines cognitive outcome in animal models of early life seizure, where males exhibit impaired hippocampal-dependent learning and memory compared with females. The physiological underpinnings of this sex effect are unclear. Cholinergic signaling is essential for the generation of hippocampal oscillations, and supplementation of cholinergic precursors prior to status epilepticus in immature male rats prevents subsequent memory deficits. We hypothesized that there are sex differences in acetylcholine circuits and their response to experimental febrile status epilepticus (eFSE). METHODS: eFSE was induced in male and female rat pups. We transversed the hippocampus of postnatal day >60 control (CTL) and eFSE rats with a 64-channel laminar silicon probe to assay cholinergic-dependent theta oscillations under urethane anesthesia. Local field potential properties were compared during (1) baseline sensory stimulation, (2) pharmacological stimulation via acetylcholine reuptake blockade, and (3) sensory stimulation after muscarinic acetylcholine receptor block (atropine). RESULTS: In all groups, a baseline tail pinch could elicit theta oscillations via corticohippocampal synaptic input. Following atropine, a tail pinch response could no longer be elicited in CTL male, CTL female, or eFSE female rats. In contrast, induced slow theta power in eFSE males after atropine was not decreased to spontaneous levels. Analysis of oscillation bandwidths revealed sex differences in acetylcholine modulation of theta frequency and slow gamma frequency and power. This study also identified significant effects of both sex and eFSE on baseline theta-gamma comodulation, indicating a loss of coupling in eFSE males and a potential gain of function in eFSE females. SIGNIFICANCE: There are differences in cholinergic modulation of theta and gamma signal coordination between male and female rats. These differences may underlie worse cognitive outcomes in males following eFSE. Promoting the efficacy of muscarinic acetylcholine signaling prior to or following early life seizures could elucidate a mechanism for the temporal discoordination of neural signals within and between hippocampus and neocortex and provide a novel therapeutic approach for improving cognitive outcomes.

2.
Epilepsy Behav ; 152: 109638, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38325075

RESUMEN

Obsessive compulsive disorder (OCD) is a comorbid condition of epilepsy and often adds to the burden of epilepsy. Both OCD and epilepsy are disorders of hyperexcitable circuits. Fronto-striatal circuit dysfunction is implicated in OCD. Prior work in our laboratory has shown that in rat pups following a series of flurothyl-induced early life seizures (ELS) exhibit frontal-lobe dysfunction along with alterations in electrographic temporal coordination between the orbitofrontal cortex (OFC) and dorsomedial striatum (DMS), circuits implicated in OCD. Here, we studied the effects of ELS in male and female rat pups on OCD-like behaviors as adults using the marble burying test (MBT). Because cannabidiol (CBD) is an effective antiseizure medication and has shown efficacy in the treatment of individuals with OCD, we also randomized rats to CBD or vehicle treatment following ELS to determine if CBD had any effect on OCD-like behaviors. While the flurothyl model of ELS did not induce OCD-like behaviors, as measured in the MBT, ELS did alter neural signaling in structures implicated in OCD and CBD had sex-dependent effects of temporal coordination in a way which suggests it may have a beneficial effect on epilepsy-related OCD.


Asunto(s)
Cannabidiol , Epilepsia , Masculino , Femenino , Animales , Ratas , Flurotilo , Imagen por Resonancia Magnética , Convulsiones/inducido químicamente , Convulsiones/tratamiento farmacológico
3.
Epilepsy Behav ; 145: 109320, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37352815

RESUMEN

Obsessive compulsive disorder (OCD) can occur comorbidly with epilepsy; both are complex, disruptive disorders that lower quality of life. Both OCD and epilepsy are disorders of hyperexcitable circuits, but it is unclear whether common circuit pathology may underlie the co-occurrence of these two neuropsychiatric disorders. Here, we induced early-life seizures (ELS) in rats to examine habit formation as a model for compulsive behaviors. Compulsive, repetitive behaviors in OCD utilize the same circuitry as habit formation. We hypothesized that rats with ELS could be more susceptible to habit formation than littermate controls, and that altered behavior would correspond to altered signaling in fronto-striatal circuits that underlie decision-making and action initiation. Here, we show instead that rats with ELS were significantly less likely to form habit behaviors compared with control rats. This behavioral difference corresponded with significant alterations to temporal coordination within and between brain regions that underpin the action to habit transition: 1) phase coherence between the lateral orbitofrontal cortex and dorsomedial striatum (DMS) and 2) theta-gamma coupling within DMS. Finally, we used cortical electrical stimulation as a model of transcranial magnetic stimulation (TMS) to show that temporal coordination of fronto-striatal circuits in control and ELS rats are differentially susceptible to potentiating and suppressive stimulation, suggesting that altered underlying circuit physiology may lead to altered response to therapeutic interventions such as TMS.


Asunto(s)
Cuerpo Estriado , Calidad de Vida , Ratas , Animales , Encéfalo , Hábitos , Convulsiones , Imagen por Resonancia Magnética
4.
Hippocampus ; 33(8): 970-992, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37096324

RESUMEN

How the development and function of neural circuits governing learning and memory are affected by insults in early life remains poorly understood. The goal of this study was to identify putative changes in cortico-hippocampal signaling mechanisms that could lead to learning and memory deficits in a clinically relevant developmental pathophysiological rodent model, Febrile status epilepticus (FSE). FSE in both pediatric cases and the experimental animal model, is associated with enduring physiological alterations of the hippocampal circuit and cognitive impairment. Here, we deconstruct hippocampal circuit throughput by inducing slow theta oscillations in rats under urethane anesthesia and isolating the dendritic compartments of CA1 and dentate gyrus subfields, their reception of medial and lateral entorhinal cortex inputs, and the efficacy of signal propagation to each somatic cell layer. We identify FSE-induced theta-gamma decoupling at cortical synaptic input pathways and altered signal phase coherence along the CA1 and dentate gyrus somatodendritic axes. Moreover, increased DG synaptic activity levels are predictive of poor cognitive outcomes. We propose that these alterations in cortico-hippocampal coordination interfere with the ability of hippocampal dendrites to receive, decode and propagate neocortical inputs. If this frequency-specific syntax is necessary for cortico-hippocampal coordination and spatial learning and memory, its loss could be a mechanism for FSE cognitive comorbidities.


Asunto(s)
Convulsiones Febriles , Estado Epiléptico , Ratas , Animales , Convulsiones Febriles/inducido químicamente , Convulsiones Febriles/complicaciones , Convulsiones Febriles/metabolismo , Aprendizaje Espacial , Hipocampo/fisiología , Corteza Entorrinal/fisiología , Estado Epiléptico/inducido químicamente , Giro Dentado/fisiología
5.
Neurobiol Dis ; 178: 106021, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36720444

RESUMEN

There is increasing human and animal evidence that brain oscillations play a critical role in the development of spatial cognition. In rat pups, disruption of hippocampal rhythms via optogenetic stimulation during the critical period for memory development impairs spatial cognition. Early-life seizures are associated with long-term deficits in spatial cognition and aberrant hippocampal oscillatory activity. Here we asked whether modulation of hippocampal rhythms following early-life seizures can reverse or improve hippocampal connectivity and spatial cognition. We used optogenetic stimulation of the medial septum to induce physiological 7 Hz theta oscillations in the hippocampus during the critical period of spatial cognition following early-life seizures. Optogenetic stimulation of the medial septum in control and rats subjected to early-life seizures resulted in precisely regulated frequency-matched hippocampal oscillations. Rat pups receiving active blue light stimulation performed better than the rats receiving inert yellow light in a test of spatial cognition. The improvement in spatial cognition in these rats was associated with a faster theta frequency and higher theta power, coherence and phase locking value in the hippocampus than rats with early-life seizures receiving inert yellow light. These findings indicate that following early life seizures, modification of hippocampal rhythms may be a potential novel therapeutic modality.


Asunto(s)
Hipocampo , Optogenética , Humanos , Ratas , Animales , Optogenética/métodos , Hipocampo/fisiología , Convulsiones/terapia , Luz , Cognición , Ritmo Teta/fisiología
6.
Epilepsy Behav ; 126: 108430, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-34902661

RESUMEN

BACKGROUND: Febrile seizures are the most common type of seizures in children. While in most children the outcome is favorable, children with febrile status epilepticus may exhibit modest cognitive impairment. Whether children with other forms of complex febrile seizure, such as repetitive febrile seizures within the same illness are at risk of cognitive deficits is not known. In this study, we used a well-established model of experimental febrile seizures in rat pups to compare the effects of febrile status epilepticus and recurrent febrile seizures on subsequent spatial cognition and anxiety. METHODS: Male and female rat pups were subjected to hyperthermic seizures at postnatal day 10 and were divided into groups of rats with continuous seizures for ≥40 min or recurrent febrile seizures. They were then tested as adults in the active avoidance and spatial accuracy tests to assess spatial learning and memory and the elevated plus maze to measure anxiety. RESULTS: Febrile status epilepticus rats demonstrated impaired spatial cognition in active avoidance and spatial accuracy and exhibited reduced anxiety-like behavior in the elevated plus maze. Rats with recurrent febrile seizures did not differ significantly from the controls on any measures. There were also significant sex-related differences with females with FSE performing far better than males with FSE in active avoidance but demonstrating a navigational learning impairment relative to CTL females in spatial accuracy. However, once learned, females with FSE performed the spatial accuracy task as well as CTL females. CONCLUSION: There is a duration-dependent effect of febrile seizures on subsequent cognitive and behavioral outcomes. Febrile status epilepticus resulted in spatial cognitive deficits and reduced anxiety-related behaviors whereas rats with recurrent febrile seizures did not differ from controls. Sex had a remarkable effect on spatial cognitive outcome where males with FSE fared worse than females with FSE. The results demonstrate that sex should be considered as a biological variable in studies evaluating the effects of seizures on the developing brain.


Asunto(s)
Disfunción Cognitiva , Convulsiones Febriles , Estado Epiléptico , Animales , Cognición , Disfunción Cognitiva/etiología , Femenino , Hipocampo , Humanos , Masculino , Aprendizaje por Laberinto , Ratas , Convulsiones/complicaciones , Convulsiones Febriles/complicaciones , Estado Epiléptico/complicaciones
7.
Epilepsia ; 62(12): 3117-3130, 2021 12.
Artículo en Inglés | MEDLINE | ID: mdl-34562024

RESUMEN

OBJECTIVE: Febrile seizures (FSs) are the most common form of seizures in children. Single short FSs are benign, but FSs lasting longer than 30 min, termed febrile status epilepticus, may result in neurological sequelae. However, there is little information about an intermediary condition, brief recurrent FSs (RFSs). The goal of this study was to determine the role of RFSs on spatial learning and memory and the properties of spontaneous hippocampal signals. METHODS: A hippocampus-dependent active avoidance task was used to assess spatial learning and memory in adult rats that underwent experimental RFSs (eRFSs) in early life compared with their littermate controls. Following completion of the task, we utilized high-density laminar probes to measure spontaneous hippocampal CA1 circuit activity under urethane anesthesia, which allowed for the simultaneous recording of input regions in CA1 associated with both CA3 and entorhinal cortex. RESULTS: RFSs did not result in deficits in the active avoidance spatial test, a hippocampus-dependent test of spatial learning and memory. However, in vivo high-density laminar electrode recordings from eRFS rats had significantly altered power and frequency expression of theta and gamma bandwidths as well as signaling efficacy along the CA1 somatodendritic axis. Thus, although eRFS modified CA1 neuronal input/output dynamics, these alterations were not sufficient to impair active avoidance spatial behavior. SIGNIFICANCE: These findings indicate that although eRFSs do not result in spatial cognitive deficits in the active avoidance task, recurrent seizures do alter the brain and result in longstanding changes in the temporal organization of the hippocampus.


Asunto(s)
Convulsiones Febriles , Estado Epiléptico , Animales , Hipocampo/fisiología , Ratas , Convulsiones/inducido químicamente , Convulsiones/complicaciones , Convulsiones Febriles/inducido químicamente , Convulsiones Febriles/complicaciones , Aprendizaje Espacial/fisiología , Estado Epiléptico/inducido químicamente , Estado Epiléptico/complicaciones
8.
Epilepsia ; 62(7): 1701-1714, 2021 07.
Artículo en Inglés | MEDLINE | ID: mdl-34002378

RESUMEN

OBJECTIVE: Early life seizures (ELSs) alter activity-dependent maturation of neuronal circuits underlying learning and memory. The pathophysiological mechanisms underpinning seizure-induced cognitive impairment are not fully understood, and critical variables such as sex and dynamic brain states with regard to cognitive outcomes have not been explored. We hypothesized that in comparison to control (CTL) rats, ELS rats would exhibit deficits in spatial cognition correlating with impaired dynamic neural signal coordination between the hippocampus and medial prefrontal cortex (mPFC). METHODS: Male and female rat pups were given 50 flurothyl-induced seizures over 10 days starting at postnatal Day 15. As adults, spatial cognition was tested through active avoidance on a rotating arena. Microwire tetrodes were implanted in the mPFC and CA1 subfield. Single cells and local field potentials were recorded and analyzed in each region during active avoidance and sleep. RESULTS: ELS males exhibited avoidance impairments, whereas female rats were unaffected. During avoidance, hippocampus-mPFC coherence was higher in CTL females than CTL males across bandwidths. In comparison to CTL males, ELS male learners exhibit increased coherence within theta bandwidth as well as altered burst-timing in mPFC cell activity. Hippocampus-mPFC coherence levels are predictive of cognitive outcome in the active avoidance spatial task. SIGNIFICANCE: Spatial cognitive outcome post-ELS is sex-dependent, as females fare better than males. ELS males that learn the task exhibit increased mPFC coherence levels at low-theta frequency, which may compensate for ELS effects on mPFC cell timing. These results suggest that coherence may serve as a biomarker for spatial cognitive outcome post-ELS and emphasize the significance of analyzing sex and dynamic cognition as variables in understanding seizure effects on the developing brain.


Asunto(s)
Encéfalo/patología , Hipocampo/patología , Red Nerviosa/patología , Corteza Prefrontal/patología , Convulsiones/patología , Animales , Reacción de Prevención , Encéfalo/fisiopatología , Región CA1 Hipocampal/patología , Cognición , Convulsivantes , Electrodos Implantados , Electroencefalografía , Femenino , Flurotilo , Masculino , Aprendizaje por Laberinto , Ratas , Ratas Sprague-Dawley , Convulsiones/inducido químicamente , Convulsiones/psicología , Caracteres Sexuales , Sueño , Percepción Espacial , Ritmo Teta
9.
Brain Stimul ; 13(6): 1535-1547, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32871261

RESUMEN

BACKGROUND: Hippocampal oscillations play a critical role in the ontogeny of allocentric memory in rodents. During the critical period for memory development, hippocampal theta is the driving force behind the temporal coordination of neuronal ensembles underpinning spatial memory. While known that hippocampal oscillations are necessary for normal spatial cognition, whether disrupted hippocampal oscillatory activity during the critical period impairs long-term spatial memory is unknown. Here we investigated whether disruption of normal hippocampal rhythms during the critical period have enduring effects on allocentric memory in rodents. OBJECTIVE/HYPOTHESIS: We hypothesized that disruption of hippocampal oscillations via artificial regulation of the medial septum during the critical period for memory development results in long-standing deficits in spatial cognition. METHODS: After demonstrating that pan-neuronal medial septum (MS) optogenetic stimulation (465 nm activated) regulated hippocampal oscillations in weanling rats we used a random pattern of stimulation frequencies to disrupt hippocampal theta rhythms for either 1Hr or 5hr a day between postnatal (P) days 21-25. Non-stimulated and yellow light-stimulated (590 nm) rats served as controls. At P50-60 all rats were tested for spatial cognition in the active avoidance task. Rats were then sacrificed, and the MS and hippocampus assessed for cell loss. Power spectrum density of the MS and hippocampus, coherences and voltage correlations between MS and hippocampus were evaluated at baseline for a range of stimulation frequencies from 0.5 to 110 Hz and during disruptive hippocampal stimulation. Unpaired t-tests and ANOVA were used to compare oscillatory parameters, behavior and cell density in all animals. RESULTS: Non-selective optogenetic stimulation of the MS in P21 rats resulted in precise regulation of hippocampal oscillations with 1:1 entrainment between stimulation frequency (0.5-110 Hz) and hippocampal local field potentials. Across bandwidths MS stimulation increased power, coherence and voltage correlation at all frequencies whereas the disruptive stimulation increased power and reduced coherence and voltage correlations with most statistical measures highly significant (p < 0.001, following correction for false detection). Rats receiving disruptive hippocampal stimulation during the critical period for memory development for either 1Hr or 5hr had marked impairment in spatial learning as measured in active avoidance test compared to non-stimulated or yellow light-control rats (p < 0.001). No cell loss was measured between the blue-stimulated and non-stimulated or yellow light-stimulated controls in either the MS or hippocampus. CONCLUSION: The results demonstrated that robust regulation of hippocampal oscillations can be achieved with non-selective optogenetic stimulation of the MS in rat pups. A disruptive hippocampal stimulation protocol, which markedly increases power and reduces coherence and voltage correlations between the MS and hippocampus during the critical period of memory development, results in long-standing spatial cognitive deficits. This spatial cognitive impairment is not a result of optogenetic stimulation-induced cell loss.


Asunto(s)
Cognición/fisiología , Período Crítico Psicológico , Hipocampo/fisiología , Memoria/fisiología , Optogenética/métodos , Aprendizaje Espacial/fisiología , Animales , Electroencefalografía/métodos , Femenino , Hipocampo/química , Masculino , Neuronas/fisiología , Ratas , Ratas Sprague-Dawley , Ritmo Teta/fisiología
10.
Hippocampus ; 30(11): 1167-1193, 2020 11.
Artículo en Inglés | MEDLINE | ID: mdl-32710688

RESUMEN

Hippocampal theta oscillations show prominent changes in frequency and amplitude depending on behavioral state or cognitive demands. How these dynamic changes in theta oscillations contribute to the spatial and temporal organization of hippocampal cells, and ultimately behavior, remain unclear. We used low-theta frequency optogenetic stimulation to pace coordination of cellular and network activity between the medial septum (MS) and hippocampus during baseline and MS stimulation while rats were at rest or performing a spatial accuracy task with a visible or hidden goal zone. Hippocampal receptivity to pan-neuronal septal stimulation at low-theta frequency was primarily determined by speed and secondarily by task demands. Competition between artificial and endogenous field potentials at theta frequency attenuated hippocampal phase preference relative to local theta, but the spike-timing activity of hippocampal pyramidal cells was effectively driven by artificial septal output, particularly during the hidden goal task. Notwithstanding temporal reorganization by artificial theta stimulation, place field properties were unchanged and alterations to spatial behavior were limited to goal zone approximation. Our results indicate that even a low-theta frequency timing signal in the septohippocampal circuit is sufficient for spatial goal finding behavior. The results also advance a mechanistic understanding of how endogenous or artificial somatodendritic timing signals relate to displacement computations during navigation and spatial memory.


Asunto(s)
Cognición/fisiología , Objetivos , Hipocampo/fisiología , Optogenética/métodos , Tabique del Cerebro/fisiología , Memoria Espacial/fisiología , Ritmo Teta/fisiología , Animales , Estimulación Eléctrica/métodos , Electrodos Implantados , Masculino , Red Nerviosa/fisiología , Ratas , Ratas Sprague-Dawley
12.
PLoS One ; 14(9): e0222066, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31498817

RESUMEN

Of the fast ionotropic synapses, glycinergic synapses are the least well understood, but are vital for the maintenance of inhibitory signaling in the brain and spinal cord. Glycinergic signaling comprises half of the inhibitory signaling in the spinal cord, and glycinergic synapses are likely to regulate local nociceptive processing as well as the transmission to the brain of peripheral nociceptive information. Here we have investigated the rapid and prolonged potentiation of glycinergic synapses in the superficial dorsal horn of young male and female mice after brief activation of NMDA receptors (NMDARs). Glycinergic inhibitory postsynaptic currents (IPSCs) evoked with lamina II-III stimulation in identified GABAergic neurons in lamina II were potentiated by bath-applied Zn2+ and were depressed by the prostaglandin PGE2, consistent with the presence of both GlyRα1- and GlyRα3-containing receptors. NMDA application rapidly potentiated synaptic glycinergic currents. Whole-cell currents evoked by exogenous glycine were also readily potentiated by NMDA, indicating that the potentiation results from altered numbers or conductance of postsynaptic glycine receptors. Repetitive depolarization alone of the postsynaptic GABAergic neuron also potentiated glycinergic synapses, and intracellular EGTA prevented both NMDA-induced and depolarization-induced potentiation of glycinergic IPSCs. Optogenetic activation of trpv1 lineage afferents also triggered NMDAR-dependent potentiation of glycinergic synapses. Our results suggest that during peripheral injury or inflammation, nociceptor firing during injury is likely to potentiate glycinergic synapses on GABAergic neurons. This disinhibition mechanism may be engaged rapidly, altering dorsal horn circuitry to promote the transmission of nociceptive information to the brain.


Asunto(s)
Glicina/metabolismo , Potenciación a Largo Plazo , Receptores de N-Metil-D-Aspartato/metabolismo , Sinapsis/fisiología , Animales , Calcio/metabolismo , Femenino , Potenciales Postsinápticos Inhibidores , Masculino , Ratones , Nocicepción/fisiología , Receptores de Glicina/metabolismo , Asta Dorsal de la Médula Espinal/citología , Asta Dorsal de la Médula Espinal/fisiología , Sinapsis/metabolismo
13.
J Healthc Manag ; 63(6): 383-394, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30418366

RESUMEN

EXECUTIVE SUMMARY: To assess the impact of military hospital expenditures on environmental services (EVS) on inpatient satisfaction, the authors collected Defense Health Agency TRICARE Inpatient Satisfaction Survey data from fiscal years 2011 through 2013, military hospital EVS spending and workload data, facility construction/renovation data, and military health system inpatient administrative claims data. Multivariate logistic regression for panel data was performed independently for medical/surgical and obstetric product lines and each satisfaction question. A statistically significant positive relationship was found between hospital EVS spending and patient satisfaction, with the highest expenditure levels generally exhibiting a greater association with satisfaction. Statistically significant increases in satisfaction with cleanliness were associated with higher levels of hospital expenditures on EVS.


Asunto(s)
Hospitales Militares/economía , Servicio de Limpieza en Hospital/economía , Pacientes Internos , Satisfacción del Paciente , Adolescente , Adulto , Anciano , Femenino , Humanos , Modelos Logísticos , Masculino , Persona de Mediana Edad , Encuestas y Cuestionarios , Estados Unidos , Adulto Joven
14.
Mil Med ; 181(7): 638-42, 2016 07.
Artículo en Inglés | MEDLINE | ID: mdl-27391616

RESUMEN

This article describes the reliability of the instruments embedded in a mental health screening instrument designed to detect risky drinking, depression, and post-traumatic stress disorder among members of the Armed Forces. The instruments were generally reliable, however, the risky drinking screen (Alcohol Use Disorders Identification Test-Consumption) had unacceptable reliability (α = 0.58). This was the first attempt to assess psychometric properties of a screening and assessment instrument widely used for members of the Armed Forces.


Asunto(s)
Adaptación Psicológica , Personal Militar/psicología , Medición de Riesgo/normas , Alcoholismo/epidemiología , Alcoholismo/psicología , Depresión/epidemiología , Depresión/psicología , Humanos , Tamizaje Masivo/métodos , Tamizaje Masivo/psicología , Tamizaje Masivo/normas , Psicometría/instrumentación , Psicometría/métodos , Reproducibilidad de los Resultados , Medición de Riesgo/métodos , Trastornos por Estrés Postraumático/epidemiología , Trastornos por Estrés Postraumático/psicología , Encuestas y Cuestionarios
15.
Neuron ; 88(5): 941-956, 2015 Dec 02.
Artículo en Inglés | MEDLINE | ID: mdl-26606998

RESUMEN

NG2-expressing glia (NG2 glia) are a uniformly distributed and mitotically active pool of cells in the central nervous system (CNS). In addition to serving as progenitors of myelinating oligodendrocytes, NG2 glia might also fulfill physiological roles in CNS homeostasis, although the mechanistic nature of such roles remains unclear. Here, we report that ablation of NG2 glia in the prefrontal cortex (PFC) of the adult brain causes deficits in excitatory glutamatergic neurotransmission and astrocytic extracellular glutamate uptake and induces depressive-like behaviors in mice. We show in parallel that chronic social stress causes NG2 glia density to decrease in areas critical to Major Depressive Disorder (MDD) pathophysiology at the time of symptom emergence in stress-susceptible mice. Finally, we demonstrate that loss of NG2 glial secretion of fibroblast growth factor 2 (FGF2) suffices to induce the same behavioral deficits. Our findings outline a pathway and role for NG2 glia in CNS homeostasis and mood disorders.


Asunto(s)
Antígenos/metabolismo , Depresión/patología , Factor 2 de Crecimiento de Fibroblastos/metabolismo , Neuroglía/metabolismo , Corteza Prefrontal/patología , Proteoglicanos/metabolismo , Estrés Psicológico/fisiopatología , Sistema de Transporte de Aminoácidos X-AG/genética , Sistema de Transporte de Aminoácidos X-AG/metabolismo , Animales , Antígenos/genética , Depresión/etiología , Toxina Diftérica/administración & dosificación , Modelos Animales de Enfermedad , Regulación hacia Abajo/genética , Conducta Exploratoria/fisiología , Factor 2 de Crecimiento de Fibroblastos/genética , Factor de Crecimiento Similar a EGF de Unión a Heparina/genética , Humanos , Potenciales de la Membrana/efectos de los fármacos , Potenciales de la Membrana/genética , Ratones , Ratones Endogámicos C57BL , Ratones Transgénicos , Neuronas/efectos de los fármacos , Neuronas/metabolismo , Fosfopiruvato Hidratasa/metabolismo , Transporte de Proteínas/efectos de los fármacos , Transporte de Proteínas/genética , Proteoglicanos/genética , Receptores de Glutamato/genética , Receptores de Glutamato/metabolismo , Transducción de Señal/efectos de los fármacos , Transducción de Señal/genética , Transmisión Sináptica/efectos de los fármacos , Transmisión Sináptica/genética
16.
J Neurosci ; 34(46): 15455-65, 2014 Nov 12.
Artículo en Inglés | MEDLINE | ID: mdl-25392512

RESUMEN

In primary sensory cortices, thalamocortical (TC) inputs can directly activate excitatory and inhibitory neurons. In vivo experiments in the main input layer (L4) of primary visual cortex (V1) have shown that excitatory and inhibitory neurons have different tuning properties. The different functional properties may arise from distinct intrinsic properties of L4 neurons, but could also depend on cell type-specific properties of the synaptic inputs from the lateral geniculate nucleus of the thalamus (LGN) onto L4 neurons. While anatomical studies identified LGN inputs onto both excitatory and inhibitory neurons in V1, their synaptic properties have not been investigated. Here we used an optogenetic approach to selectively activate LGN terminal fields in acute coronal slices containing V1, and recorded monosynaptic currents from excitatory and inhibitory neurons in L4. LGN afferents made monosynaptic connections with pyramidal (Pyr) and fast-spiking (FS) neurons. TC EPSCs on FS neurons were larger and showed steeper short-term depression in response to repetitive stimulation than those on Pyr neurons. LGN inputs onto Pyr and FS neurons also differed in postsynaptic receptor composition and organization of presynaptic release sites. Together, our results demonstrate that LGN input onto L4 neurons in mouse V1 have target-specific presynaptic and postsynaptic properties. Distinct mechanisms of activation of feedforward excitatory and inhibitory neurons in the main input layer of V1 are likely to endow neurons with different response properties to incoming visual stimuli.


Asunto(s)
Cuerpos Geniculados/fisiología , Sinapsis/fisiología , Corteza Visual/citología , Corteza Visual/fisiología , Animales , Potenciales Postsinápticos Excitadores/fisiología , Femenino , Técnicas In Vitro , Masculino , Ratones , Neuronas/fisiología , Optogenética , Células Piramidales/fisiología
17.
J Neurosci ; 33(9): 4181-91, 2013 Feb 27.
Artículo en Inglés | MEDLINE | ID: mdl-23447625

RESUMEN

Thalamocortical circuits are central to sensory and cognitive processing. Recent work suggests that the thalamocortical inputs onto L4 and L6, the main input layers of neocortex, are activated differently by visual stimulation. Whether these differences depend on layer-specific organization of thalamocortical circuits; or on specific properties of synapses onto receiving neurons is unknown. Here we combined optogenetic stimulation of afferents from the visual thalamus and paired recording electrophysiology in L4 and L6 of rat primary visual cortex to determine the organization and plasticity of thalamocortical synapses. We show that thalamocortical inputs onto L4 and L6 differ in synaptic dynamics and sensitivity to visual drive. We also demonstrate that the two layers differ in the organization of thalamocortical and recurrent intracortical connectivity. In L4, a significantly larger proportion of excitatory neurons responded to light activation of thalamocortical terminal fields than in L6. The local microcircuit in L4 showed a higher degree of recurrent connectivity between excitatory neurons than the microcircuit in L6. In addition, L4 recurrently connected neurons were driven by thalamocortical inputs of similar magnitude indicating the presence of local subnetworks that may be activated by the same axonal projection. Finally, brief manipulation of visual drive reduced the amplitude of light-evoked thalamocortical synaptic currents selectively onto L4. These data are the first direct indication that thalamocortical circuits onto L4 and L6 support different aspects of cortical function through layer-specific synaptic organization and plasticity.


Asunto(s)
Cuerpos Geniculados/fisiología , Plasticidad Neuronal/fisiología , Neuronas/fisiología , Sinapsis/fisiología , Corteza Visual/citología , Vías Visuales/fisiología , Análisis de Varianza , Animales , Animales Recién Nacidos , Biofisica , Channelrhodopsins , Estimulación Eléctrica , Potenciales Postsinápticos Excitadores/fisiología , Proteínas Fluorescentes Verdes/genética , Proteínas Fluorescentes Verdes/metabolismo , Técnicas In Vitro , Optogenética , Técnicas de Placa-Clamp , Estimulación Luminosa , Ratas , Ratas Transgénicas , Privación Sensorial/fisiología , Corteza Visual/fisiología
18.
Mil Med ; 178(2): 180-95, 2013 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-23495464

RESUMEN

OBJECTIVES: This study identifies predictors of prescription drug misuse among U.S. active duty service members (ADSM). The 2008 Department of Defense Survey of Health-Related Behaviors (HRB) Among Active Duty Military Personnel indicated that ADSM misuse pain relievers, tranquilizers, sedatives, and stimulants at levels ranging from 2% to 17%. METHODS: Secondary, multivariate analyses of HRB survey data examined predictors of self-reported prescription drug misuse for 4 distinct drug categories. RESULTS: Receipt of a pain reliever prescription in the past month, year, or previous year were strong predictors (adjusted odds ratio above 2.0) of misuse for all drug categories; receipt of a prescription for anxiety or depression medication in the past year was the strongest predictor of sedative misuse (adjusted odds ratio = 4.46, 95% confidence intervals 3.18-6.24). Absence of a drug testing program was significantly related to the likelihood of drug misuse for all drug categories. CONCLUSIONS: ADSM with a history of treatment for pain and mood disorders, and who self-report headaches, sleep disorders, and fatigue are at higher risk for misusing prescription drugs, perhaps in an effort to self-manage symptoms. The results should be interpreted as a starting place for future exploration, not as the sole basis for policy or program development.


Asunto(s)
Sobredosis de Droga/epidemiología , Conductas Relacionadas con la Salud , Personal Militar/estadística & datos numéricos , Encuestas Epidemiológicas , Humanos , Análisis Multivariante , Estados Unidos , United States Department of Defense
19.
Ethn Dis ; 23(4): 508-17, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-24392616

RESUMEN

BACKGROUND: The Communities Putting Prevention to Work: Chronic Disease Self-Management Program (CDSMP) Initiative funded grantees in 45 states, the District of Columbia and Puerto Rico to implement and expand delivery of CDSMP to older adults. We examine whether there are differences in the enrollment and completion rates of members of racial and ethnic minority groups and what sites have done to enhance their delivery of the CDSMP to such groups. METHOD: This study used a multi-method approach including: site visits to 6 states, telephone interviews with the 47 program grantees and delivery sites, review of program reports, and analysis of administrative data on participants, completers, workshops and leaders. RESULTS: Grantees served 89,861 participants, including 56.3% who self-identified as White, 17.3% as Black, 5.0% as other/multi-racial, 3.2% as Asian/Asian Americans, 1.4% as American Indian/Alaskans, .8% as Native Hawaiian/Pacific Islanders, and 16.0% individuals of unknown race. Overall, completion rates averaged 74.5%, with Native Hawaiian/Pacific Islanders completing workshops at a higher rate (90.6%) than other groups. Completion rates for participants aged > or = 75 were higher than for younger participants. Senior centers, health care organizations, and residential facilities served 63.1% of the participants. CONCLUSIONS: Grantees have successfully delivered CDSMP to racially and ethnically diverse participants in a range of settings. As the Administration for Community Living/Administration on Aging (ACL/AoA) grantees have demonstrated, CDSMP can be brought to scale by community organizations, partnerships and networks to reach diverse populations in diverse settings. The program can be a significant tool for addressing health disparities and empowering racial/ethnic minorities to take charge, promote better health and self-management of chronic conditions.


Asunto(s)
Enfermedad Crónica/etnología , Enfermedad Crónica/terapia , Etnicidad/estadística & datos numéricos , Promoción de la Salud/organización & administración , Autocuidado , Anciano , Femenino , Humanos , Entrevistas como Asunto , Masculino , Persona de Mediana Edad , Cooperación del Paciente , Evaluación de Programas y Proyectos de Salud , Estados Unidos
20.
J Neurosci ; 28(48): 12691-9, 2008 Nov 26.
Artículo en Inglés | MEDLINE | ID: mdl-19036962

RESUMEN

Animals with a neonatal ventral hippocampal lesion (NVHL) develop abnormal behaviors during or after adolescence, suggesting that early insults can have delayed consequences. Many of these behaviors depend on the prefrontal cortex (PFC), and we have reported that PFC pyramidal neurons of adult rats with an NVHL respond to stimulation of the ventral tegmental area with an increase in firing instead of the characteristic decrease. As the dopamine modulation of cortical interneurons matures during adolescence, these findings raise the possibility that maturation of local inhibitory circuits within the PFC may have been altered in NVHL rats. Here, we assessed the state of PFC interneurons in NVHL rats with in situ hybridization measures of the mRNAs for the calcium binding protein parvalbumin (PV) and the GABA synthesizing enzyme GAD(67), as well as with electrophysiological measures of interneuron function. Although no differences were observed with PV or GAD(67), whole-cell recordings in slices revealed abnormal responses to the D(2) agonist quinpirole in interneurons from NVHL rats. The loss of D(2) modulation of local inhibition in slices from NVHL rats was also evident in the absence of a lasting component in the D(2) attenuation of excitatory synaptic responses in pyramidal neurons, which in sham treated rats was picrotoxin sensitive. The results suggest that the neonatal lesion causes improper maturation, but not loss, of PFC interneurons during adolescence, a finding consistent with current interpretations of imaging data in schizophrenia that suggest a hyperactive, "noisy" cortex underlying dysfunction in the PFC and other cortical areas.


Asunto(s)
Envejecimiento/fisiología , Hipocampo/anomalías , Hipocampo/lesiones , Interneuronas/metabolismo , Neurogénesis/fisiología , Corteza Prefrontal/fisiopatología , Animales , Animales Recién Nacidos , Biomarcadores/análisis , Biomarcadores/metabolismo , Desnervación , Agonistas de Dopamina/farmacología , Glutamato Descarboxilasa/genética , Hipocampo/fisiopatología , Masculino , Inhibición Neural/fisiología , Vías Nerviosas/anomalías , Vías Nerviosas/lesiones , Vías Nerviosas/fisiopatología , Técnicas de Cultivo de Órganos , Parvalbúminas/genética , Técnicas de Placa-Clamp , Corteza Prefrontal/citología , Corteza Prefrontal/crecimiento & desarrollo , Células Piramidales/efectos de los fármacos , Células Piramidales/metabolismo , ARN Mensajero/análisis , ARN Mensajero/metabolismo , Ratas , Ratas Sprague-Dawley , Esquizofrenia/etiología , Esquizofrenia/metabolismo , Esquizofrenia/fisiopatología , Ácido gamma-Aminobutírico/biosíntesis
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