Widespread co-release of glutamate and GABA throughout the mouse brain.

Several brain neuronal populations transmit both the excitatory and inhibitory neurotransmitters, glutamate, and GABA. However, it remains largely unknown whether these opposing neurotransmitters are co-released simultaneously or are independently transmitted at different times and locations. By recording from acute mouse brain slices, we observed biphasic miniature postsynaptic currents, i.

Prevalent co-release of glutamate and GABA throughout the mouse brain.

Several neuronal populations in the brain transmit both the excitatory and inhibitory neurotransmitters, glutamate, and GABA, to downstream neurons. However, it remains largely unknown whether these opposing neurotransmitters are co-released onto the same postsynaptic neuron simultaneously or are independently transmitted at different time and locations (called co-transmission). Here, using whole-cell patch-clamp recording on acute mouse brain slices, we observed biphasic miniature postsynaptic currents, i.

Sensitive genetically encoded sensors for population and subcellular imaging of cAMP in vivo.

Cyclic adenosine monophosphate (cAMP) signaling integrates information from diverse G-protein-coupled receptors, such as neuromodulator receptors, to regulate pivotal biological processes in a cellular-specific and subcellular-specific manner. However, in vivo cellular-resolution imaging of cAMP dynamics remains challenging. Here, we screen existing genetically encoded cAMP sensors and further develop the best performer to derive three improved variants, called cAMPFIREs.

Effectiveness of acute post-operative pain management by the acute pain service.

Background: Analgesia by specialists with formal training in pain management could be more effective, to find out, the results of a team of an acute pain service will be determined.

Methods: Retrospective study (n = 108) of post-operative (POP) analgesia; two evaluations were taken: before starting analgesics in the immediate POP period and the second at 24 h. A multivariate analysis was performed to establish independent risk factors associated with the effectiveness of the treatment.

High-fidelity, efficient, and reversible labeling of endogenous proteins using CRISPR-based designer exon insertion.

Precise and efficient insertion of large DNA fragments into somatic cells using gene editing technologies to label or modify endogenous proteins remains challenging. Non-specific insertions/deletions (INDELs) resulting from the non-homologous end joining pathway make the process error-prone. Further, the insert is not readily removable.

Regional Anesthesia. An Alternative to General Anesthesia in the Management of Neonatal Testicular Torsion.

We report a case of a 1-day-old male newborn with neonatal testicular torsion, in whom an immediate orchiectomy with prophylactic orchidopexy under caudal regional anesthesia was practiced. The aim of this report is to propose early surgical intervention with caudal regional anesthesia as an alternative in order to avoid possible side effects related to general anesthesia and the complications related to a missed asynchronous torsion of the contralateral testis.

Loss of Brain-Derived Neurotrophic Factor Mediates Inhibition of Hippocampal Long-Term Potentiation by High-Intensity Sound.

Exposure to noise produces cognitive and emotional disorders, and recent studies have shown that auditory stimulation or deprivation affects hippocampal function. Previously, we showed that exposure to high-intensity sound (110 dB, 1 min) strongly inhibits Schaffer-CA1 long-term potentiation (LTP). Here we investigated possible mechanisms involved in this effect.

Modeling Hippocampal CA1 Gabaergic Synapses of Audiogenic Rats.

Wistar Audiogenic Rats (WARs) are genetically susceptible to sound-induced seizures that start in the brainstem and, in response to repetitive stimulation, spread to limbic areas, such as hippocampus. Analysis of the distribution of interevent intervals of GABAergic inhibitory postsynaptic currents (IPSCs) in CA1 pyramidal cells showed a monoexponential trend in Wistar rats, suggestive of a homogeneous population of synapses, but a biexponential trend in WARs. Based on this, we hypothesize that there are two populations of GABAergic synaptic release sites in CA1 pyramidal neurons from WARs.

Alterations in brainstem auditory processing, the acoustic startle response and sensorimotor gating of startle in Wistar audiogenic rats (WAR), an animal model of reflex epilepsies.

While acute audiogenic seizures in response to acoustic stimulus appear as an alteration in sensory-motor processing in the brainstem, the repetition of the stimulus leads to the spread of epileptic activity to limbic structures. Here, we investigated whether animals of the Wistar Audiogenic Rat (WAR) strain, genetically selected by inbreeding for seizure susceptibility, would have alterations in their auditory response, assessed by the auditory brainstem responses (ABR) and sensory-motor gating, measured as pre-pulse inhibition (PPI), which could be related to their audiogenic seizures susceptibility or severity. We did not find differences between the amplitudes and latencies of ABR waves in response to clicks for WARs when compared to Wistars.

Increased hippocampal GABAergic inhibition after long-term high-intensity sound exposure.

Exposure to loud sounds is related to harmful mental and systemic effects. The hippocampal function can be affected to either high-intensity sound exposure or long-term sound deprivation. We previously showed that hippocampal long-term potentiation (LTP) is inhibited after ten days of daily exposure to 2 minutes of high-intensity noise (110 dB), in the hippocampi of Wistar rats.

Intrinsic and synaptic properties of hippocampal CA1 pyramidal neurons of the Wistar Audiogenic Rat (WAR) strain, a genetic model of epilepsy.

Despite the many studies focusing on epilepsy, a lot of the basic mechanisms underlying seizure susceptibility are mainly unclear. Here, we studied cellular electrical excitability, as well as excitatory and inhibitory synaptic neurotransmission of CA1 pyramidal neurons from the dorsal hippocampus of a genetic model of epilepsy, the Wistar Audiogenic Rat (WARs) in which limbic seizures appear after repeated audiogenic stimulation. We examined intrinsic properties of neurons, as well as EPSCs evoked by Schaffer-collateral stimulation in slices from WARs and Wistar parental strain.

Long-term high-intensity sound stimulation inhibits h current (I ) in CA1 pyramidal neurons.

Afferent neurotransmission to hippocampal pyramidal cells can lead to long-term changes to their intrinsic membrane properties and affect many ion currents. One of the most plastic neuronal currents is the hyperpolarization-activated cationic current (I ), which changes in CA1 pyramidal cells in response to many types of physiological and pathological processes, including auditory stimulation. Recently, we demonstrated that long-term potentiation (LTP) in rat hippocampal Schaffer-CA1 synapses is depressed by high-intensity sound stimulation.

Interplay of activation kinetics and the derivative conductance determines resonance properties of neurons.

In a neuron with hyperpolarization activated current (I_{h}), the correct input frequency leads to an enhancement of the output response. This behavior is known as resonance and is well described by the neuronal impedance. In a simple neuron model we derive equations for the neuron's resonance and we link its frequency and existence with the biophysical properties of I_{h}.

Non-Decaying postsynaptics potentials and delayed spikes in hippocampal pyramidal neurons generated by a zero slope conductance created by the persistent Na current.

The negative slope conductance created by the persistent sodium current (I) prolongs the decay phase of excitatory postsynaptic potentials (EPSPs). In a recent study, we demonstrated that this effect was due to an increase of the membrane time constant. When the negative slope conductance opposes completely the positive slope conductances of the other currents it creates a zero slope conductance region.

The role of negative conductances in neuronal subthreshold properties and synaptic integration.

Based on passive cable theory, an increase in membrane conductance produces a decrease in the membrane time constant and input resistance. Unlike the classical leak currents, voltage-dependent currents have a nonlinear behavior which can create regions of negative conductance, despite the increase in membrane conductance (permeability). This negative conductance opposes the effects of the passive membrane conductance on the membrane input resistance and time constant, increasing their values and thereby substantially affecting the amplitude and time course of postsynaptic potentials at the voltage range of the negative conductance.

A Negative Slope Conductance of the Persistent Sodium Current Prolongs Subthreshold Depolarizations.

Neuronal subthreshold voltage-dependent currents determine membrane properties such as the input resistance (R) and the membrane time constant (τ) in the subthreshold range. In contrast with classical cable theory predictions, the persistent sodium current (I), a non-inactivating mode of the voltage-dependent sodium current, paradoxically increases R and τ when activated. Furthermore, this current amplifies and prolongs synaptic currents in the subthreshold range.

Corrigendum: Equalizes Membrane Input Resistance in a Heterogeneous Population of Fusiform Neurons in the Dorsal Cochlear Nucleus.

[This corrects the article on p. 249 in vol. 10, PMID: 27833532.

Equalizes Membrane Input Resistance in a Heterogeneous Population of Fusiform Neurons in the Dorsal Cochlear Nucleus.

In a neuronal population, several combinations of its ionic conductances are used to attain a specific firing phenotype. Some neurons present heterogeneity in their firing, generally produced by expression of a specific conductance, but how additional conductances vary along in order to homeostatically regulate membrane excitability is less known. Dorsal cochlear nucleus principal neurons, fusiform neurons, display heterogeneous spontaneous action potential activity and thus represent an appropriate model to study the role of different conductances in establishing firing heterogeneity.

High doses of salicylate reduces glycinergic inhibition in the dorsal cochlear nucleus of the rat.

High doses of salicylate induce reversible tinnitus in experimental animals and humans, and is a common tinnitus model. Salicylate probably acts centrally and induces hyperactivity in specific auditory brainstem areas like the dorsal cochlear nucleus (DCN). However, little is known about the effect of high doses of salicylate in synapses and neurons of the DCN.

Dynamic range of vertebrate retina ganglion cells: importance of active dendrites and coupling by electrical synapses.

The vertebrate retina has a very high dynamic range. This is due to the concerted action of its diverse cell types. Ganglion cells, which are the output cells of the retina, have to preserve this high dynamic range to convey it to higher brain areas.

Acetabular labral tears and cartilage lesions of the hip: indirect MR arthrographic correlation with arthroscopy--a preliminary study.

Objective: The purpose of this study was to assess the diagnostic correlation between indirect MR arthrography, conventional MRI, and arthroscopy in acetabular labral and cartilage lesions of the hip.

Materials And Methods: Fourteen patients who underwent conventional and indirect MR arthrography with arthroscopic correlation were studied over the course of 18 months. MR studies were performed on a 1.

Palliative sedation in Latin America: survey on practices and attitudes.

Introduction: Palliative sedation (PS) is the subject of ethical and legal debates worldwide. Statistics of its utilization are available in developed countries; however, in Latin America, these data are scarcely known. The purpose of this research was to determine the practices and attitudes of palliativists in Latin America towards PS.