Journal: PLoS ONE

Article Title: Norepinephrine Drives Persistent Activity in Prefrontal Cortex via Synergistic α1 and α2 Adrenoceptors

doi: 10.1371/journal.pone.0066122

Figure Lengend Snippet: (A) A typical trace from a pyramidal neuron showing minimal response to bath application of NE (10 µM) (left panel). Co-application of NE and the selective HCN channel blocker ZD7288 (30 µM) in the bath solution in the same neuron significantly enhanced the NE-induced response (n = 12, right panel). (B) Quantitative effects of bath ZD7288 on firing frequency and amplitude of plateau potentials of NE-evoked response. (C) A threshold dose of NE (2.5 µM) induced afterdepolarization and short sustained firing (Left, without ZD7288, n = 5). In another group of neurons with ZD7288 in the recording pipette, NE induced strong persistent firing (Right, ZD7288 in pipette, n = 5). (D) Quantitative effects of intracellular ZD7288 on the firing frequency and amplitude of plateau potentials. (E) Sample traces of current step-evoked membrane potential responses before (control) and after ZD7288 application showing an increase in voltage responses (response to 40 pA current step shown in red) (left panel, n = 7). Current step stimulation from -140 pA to a maximum of 40 pA with 20 pA increments. Right: Membrane potential response to a -140 pA current step in control and in the presence of ZD7288. Note that the depolarizing membrane potential sag, a characteristic feature of HCN channel activation, was completely suppressed by ZD7288. (F) Input resistance (calculated at −200 pA) and number of spikes during the 40 pA current pulse (500 ms) before and after ZD7288 administration (n = 7). Values are mean ± SEM. ** p<0.01; *** p<0.001.

Article Snippet: All drugs were purchased from Sigma (Oakville, Ontario, Canada) except 6-methyl-2-(phenylethynyl)pyridine (MPEP), CGP 54626, 4-[1-Hydroxy-2-[(1-methylethyl) amino]ethyl]-1,2-benzenediol hydrochloride (isoproterenol) and ZD7288 which were purchased from Tocris (Tocris Bioscience, Ellisville, MO), propranolol from EMD biosciences and TTX from Alomone Labs (Jerusalem, Israel).

Techniques: Transferring, Activation Assay

Journal: PLoS ONE

Article Title: Norepinephrine Drives Persistent Activity in Prefrontal Cortex via Synergistic α1 and α2 Adrenoceptors

doi: 10.1371/journal.pone.0066122

Figure Lengend Snippet: (A) and (B) Quantitative effects of bath and in-pipette ZD7288 (30 µM) on responses of PFC pyramidal neurons to a threshold dose of DHPG (2 µM). (C), (D) and (E) Sample traces showing clonidine-sensitive Ih currents (E) at different membrane voltages obtained by subtracting current responses to voltage steps after bath application of clonidine (10 µM) (D) from pre-drug control (C). Hyperpolarization-evoked Ih currents were inhibited by clonidine. Ih current responses were evoked by hyperpolarization voltage steps (duration 2.5 s) from −50 mV to –110 mV in 10 mV increments. (F) Steady state I-V relationship of the Ih current in the absence (Control) and presence of clonidine. Instantaneous currents were subtracted. Ih was inhibited by clonidine (10–20 µM) at different membrane voltages. (G) Representative traces showing that the response of prefrontal pyramidal neurons to threshold doses of DHPG (2 µM, left panels) are enhanced by co-application of the α2 adrenoceptor agonist clonidine (10 µM, n = 5, right panel). (H) Quantitative effects of clonidine on DHPG-induced firing frequency and amplitude of plateau potentials. Values in A, B, F and H are mean ± SEM. * p<0.05; ** p<0.01; *** p<0.001.

Article Snippet: All drugs were purchased from Sigma (Oakville, Ontario, Canada) except 6-methyl-2-(phenylethynyl)pyridine (MPEP), CGP 54626, 4-[1-Hydroxy-2-[(1-methylethyl) amino]ethyl]-1,2-benzenediol hydrochloride (isoproterenol) and ZD7288 which were purchased from Tocris (Tocris Bioscience, Ellisville, MO), propranolol from EMD biosciences and TTX from Alomone Labs (Jerusalem, Israel).

Techniques: Transferring

Journal: PLoS ONE

Article Title: Norepinephrine Drives Persistent Activity in Prefrontal Cortex via Synergistic α1 and α2 Adrenoceptors

doi: 10.1371/journal.pone.0066122

Figure Lengend Snippet: (A), (C) and (E) Threshold doses of CCh (0.5–2.5 µM) induce afterdepolarization potentials or short sustained firing (left panel). NE, clonidine and ZD7288 significantly enhanced the muscarinic response in pyramidal neurons of the prefrontal cortex (right panel). (B), (D) and (F) Quantitative effects of NE (n = 5), clonidine (n = 6) or ZD7288 (n = 6) on CCh-induced firing frequency and amplitude of plateau potentials. Values are mean ± SEM. ** p<0.01. *** p<0.001.

Article Snippet: All drugs were purchased from Sigma (Oakville, Ontario, Canada) except 6-methyl-2-(phenylethynyl)pyridine (MPEP), CGP 54626, 4-[1-Hydroxy-2-[(1-methylethyl) amino]ethyl]-1,2-benzenediol hydrochloride (isoproterenol) and ZD7288 which were purchased from Tocris (Tocris Bioscience, Ellisville, MO), propranolol from EMD biosciences and TTX from Alomone Labs (Jerusalem, Israel).

Techniques:

Journal: iScience

Article Title: Developmental regulation of thalamus-driven pauses in striatal cholinergic interneurons

doi: 10.1016/j.isci.2022.105332

Figure Lengend Snippet: Developmental increase in I h expression in ChIs contributes to postnatal reductions in pause length (A) Correlations between HCN current magnitude and PS at P10, P28, and P100. Current calculated as difference between instantaneous and steady-state current following −60 mV hyperpolarizing voltage step from −60 mV holding potential (see B). Linear regressions: P10 R 2 = 0.0887, p = 0.104, n = 31(10); P28 R 2 = 0.0248, p = 0.442, n = 29(11); P100 R 2 <0.0001, p = 0.972, n = 31(15). (B) Sample voltage-clamp trace shows I h current evoked by hyperpolarizing step. I h is abolished by superfusion of HCN blocker ZD7288 (ZD) (1 μM). (C) Pre-incubation in ZD (1 μM) increases PSs at P28 and P100 but has no effect at P10. Pairs of samples were analyzed by Mann-Whitney U tests followed by correction for multiple comparisons using the Bonferroni-Dunn method. P10 corrected p>0.9999, U = 30; P28 p = 0.00296, U = 4; P100 p = 0.0200, U = 45. P10 n = 7 cells (ACSF), 9 cells (ZD), (4 mice); P28 n = 8, 9 (4); P100 n = 13, 16 (5). Dotted line represents PS = 1. Filled circles represent cells with significant pause responses. Proportion of pausing cells (veh, ZD; X 2 p value): P10 (100%, 89%; 0.362); P28 (38%, 78%; 0.0921); P100 (55%, 72%; 0.331). (D) Average basal firing rates of ChIs incubated in vehicle versus ZD. Data analyzed by two-way ANOVA with Bonferroni’s multiple comparisons test: age x drug F(2, 57) = 2.238, p = 0.116; age F(2, 57) = 3.344, p = 0.0423; drug F(1, 57) = 0.464, p = 0.499. P10 vehicle versus ZD p>0.999; P28 p>0.999; P100 p = 0.0799.

Article Snippet: ZD7288 (ZD) , Tocris , Cat#:1000.

Techniques: Expressing, Incubation, MANN-WHITNEY

Journal: iScience

Article Title: Developmental regulation of thalamus-driven pauses in striatal cholinergic interneurons

doi: 10.1016/j.isci.2022.105332

Figure Lengend Snippet:

Article Snippet: ZD7288 (ZD) , Tocris , Cat#:1000.

Techniques: Recombinant, Software