Journal: PLoS ONE

Article Title: The Involvement of Voltage-Operated Calcium Channels in Somato-Dendritic Oxytocin Release

doi: 10.1371/journal.pone.0025366

Figure Lengend Snippet: ( A ) Isolated magnocellular neurons were identified as either vasopressin or oxytocin by their presence or absence of the GFP signal. Scale bar = 10 µm. ( B ) The current-voltage relationships show no difference between whole-cell calcium currents (WCCC) of vasopressin and oxytocin neurons (n = 20 each). ( C ) Normalized conductance (G/G max , fitted using Boltzmann equation) showed no significant change with or without TG. ( D ) Examples of two neurons (both oxytocin neurons), one vehicle treated (•) and one 50 min after pre-treating with thapsigargin (○). The steady-state Ca 2+ current is plotted against time following treatment with channel toxins (in order: 1 µM nicardipine; 200 nM ω-agatoxin IV; 500 nM ω-conotoxin GVIA). The current measured after each toxin was subtracted from that evoked before each treatment to determine the current carried by L-, P/Q- and N-type channels. The remaining current was attributed to R-type channels. ( E ) Examples of N-, L- and WCCC elicited by voltage steps in controls and TG treated cells. ( F ) The resulting current density for each current type normalised for the peak maximal current was averaged (n = 5) to give the average current density from neurons treated with vehicle or thapsigargin. ( G ) In a subsequent experiment L- or N-type channel toxins were administered, alternating the order (n = 5 for each condition). Mean±S.E.M are shown and compared by t-test. * P <0.05 vs control.

Article Snippet: The channel blockers used were: L-type, 1 µM nicardipine (Sigma-Aldrich, UK); P/Q-type, 0.2 µM ω-agatoxin IVA (Alomone Labs, Jerusalem, Israel); N-type, 0.5 µM ω-conotoxin GVIA (Alomone Labs, Jerusalem, Israel); R-type, 0.02 µM SNX 482 (Alomone Labs, Jerusalem, Israel).

Techniques: Isolation

Journal: PLoS ONE

Article Title: New In Vitro Phenotypic Assay for Epilepsy: Fluorescent Measurement of Synchronized Neuronal Calcium Oscillations

doi: 10.1371/journal.pone.0084755

Figure Lengend Snippet: Summary of the compounds and antiepileptic drugs evaluated in the calcium oscillations assay.

Article Snippet: Diazepam was from Fragon; phenytoin from Fluka; conotoxin GVIA and TTX from Alomone Labs; gabapentin from TCI Chemicals; and levetiracetam and retigabine were synthetized at UCB.

Techniques:

Journal: Stem Cell Research & Therapy

Article Title: Conditionally immortalized stem cell lines from human spinal cord retain regional identity and generate functional V2a interneurons and motorneurons

doi: 10.1186/scrt220

Figure Lengend Snippet: SPC-01 generates functional neurons. (a) Preincubation with Cd 2+ (100 μ M ) together with Ni 2+ (50 μ M ), for 5 minutes significantly reduced the [Ca 2+ ] i responses induced by K + in all cells tested by 93% ± 9.2% ( n = 5), indicating the involvement of voltage-activated Ca 2+ channels in depolarization-induced Ca 2+ entry. (b) The specific L-type Ca 2+ channel blocker nicardipine (1 μ M ) reduced the [Ca 2+ ] i responses by 28% ± 7% ( n = 5; P = 0.002). The trace in (c) shows the [Ca 2+ ] i responses observed in a selected SPC-01-derived neuron induced by 50 m M K + , preincubated for 2 minutes with Ω -GVIA (800 n M ) and then stimulated with K + . After a washout of 10 minutes, the same cells were subjected to K + to observe recovery. Similarly, the effect of the P/Q-Ca 2+ channel blocker, Ω -Aga-IVA, 300 n M was tested before and during stimulation with high K + (d) . After washout of the toxin, the [Ca 2+ ] i response was shown to be reversible. The histogram (e) summarizes the results presented in (c) and (d) . The resting [Ca 2+ ] i level in these cells is indicated as basal. The results are expressed as mean ± SEM; n = 4 (Ω-GVIA) and n = 5 (Ω-Aga-IVA). Asterisks indicate the statistical significance ( P > 0.05) versus control K + stimulus.

Article Snippet: Sandimmune (Novartis Pharma AG, Basel, Switzerland); Immuran (GlaxoSmith-Kline); Solu-Medrol (Pfizer, Puurs, Belgium); Fura-2 AM 1 m M solution in anhydrous DMSO and Pluronic F-127 (30% stock in distilled water) (Molecular Probes, USA); ω-Aga Toxin IVA (ω-Aga IVA), and ω-conotoxin GVIA (ω-GVIA) (Alomone Labs Ltd. Jerusalem, Israel).

Techniques: Functional Assay, Derivative Assay