The role of galanin receptors in anticonvulsant effects of low-frequency stimulation in perforant path–kindled rats

The effect of fasciotomy on muscle tension (measured by a force transducer attached to the tendon) and interstitial fluid pressure (measured by Wick catheters in the muscle belly) was studied in the anterolateral compartments of 13 dog hindlimbs. Muscle tension and pressure were monitored in the tibialis cranialis muscle after low- and high-frequency stimulation of the peroneal nerve to produce twitch- and tetanic-type contractions. Fasciotomy decreased muscle force during the low-frequency stimulation by 16% (35.3 +/- 4.9 to 28.4 +/- 3.9 N) and during the high-frequency stimulation by 10% (60.8 %/- 4.9 to 54.8 +/- 3.9 N). Muscle pressure decreased 50% after fasciotomy under both conditions, 15 +/- 2 to 6 +/- 1 mmHg and 84 +/- 17 to 41 +/- 8 mmHg), respectively. Repeated functional evaluations during the testing procedure indicated that muscle fatigue was not a major factor in these results. It was concluded that fascia is important in the development of muscle tension and changes in interstitial pressure. Furthermore, the results raised questions concerning the merits of performing a fasciotomy for athletes with a compartment syndrome.

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The antiepileptogenic effect of low-frequency stimulation on perforant path kindling involves changes in regulators of G-protein signaling in rat

Journal of the Neurological Sciences ◽

10.1016/j.jns.2017.02.047 ◽

2017 ◽

Vol 375 ◽

pp. 450-459 ◽

Cited By ~ 7

Author(s):

Simin Namvar ◽

Yaghoub Fathollahi ◽

Mohammad Javan ◽

Maryam Zeraati ◽

Mohammad Mohammad-Zadeh ◽

...

Keyword(s):

G Protein ◽

Low Frequency ◽

Perforant Path ◽

G Protein Signaling ◽

Protein Signaling ◽

Low Frequency Stimulation ◽

Frequency Stimulation

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Long-Term Depression Is Not Induced by Low-Frequency Stimulation in Rat Visual CortexIn Vivo: A Possible Preventing Role of Endogenous Brain-Derived Neurotrophic Factor

Journal of Neuroscience ◽

10.1523/jneurosci.23-09-03761.2003 ◽

2003 ◽

Vol 23 (9) ◽

pp. 3761-3770 ◽

Cited By ~ 42

Author(s):

Bin Jiang ◽

Yukio Akaneya ◽

Yoshio Hata ◽

Tadaharu Tsumoto

Keyword(s):

Neurotrophic Factor ◽

Low Frequency ◽

Brain Derived Neurotrophic Factor ◽

Long Term Depression ◽

Low Frequency Stimulation ◽

Frequency Stimulation

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Serine/threonine protein phosphatases have no role in the inhibitory effects of low-frequency stimulation in perforant path kindling acquisition in rats

Neuroscience Letters ◽

10.1016/j.neulet.2009.01.001 ◽

2009 ◽

Vol 451 (3) ◽

pp. 266-269 ◽

Cited By ~ 2

Author(s):

Mehdi Sadegh ◽

Javad Mirnajafi-Zadeh ◽

Vahid Sheibani

Keyword(s):

Protein Phosphatases ◽

Low Frequency ◽

Perforant Path ◽

Inhibitory Effects ◽

Low Frequency Stimulation ◽

Frequency Stimulation

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Effect of low frequency stimulation of perforant path on kindling rate and synaptic transmission in the dentate gyrus during kindling acquisition in rats

Epilepsy Research ◽

10.1016/j.eplepsyres.2007.05.003 ◽

2007 ◽

Vol 75 (2-3) ◽

pp. 154-161 ◽

Cited By ~ 31

Author(s):

Mohammad Mohammad-Zadeh ◽

Javad Mirnajafi-Zadeh ◽

Yaghoub Fathollahi ◽

Mohammad Javan ◽

Parviz Ghorbani ◽

...

Keyword(s):

Synaptic Transmission ◽

Dentate Gyrus ◽

Low Frequency ◽

Perforant Path ◽

Low Frequency Stimulation ◽

Frequency Stimulation ◽

Stimulation Of

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Low-frequency stimulation induces long-term depression and slow onset long-term potentiation at perforant path-dentate gyrus synapses in vivo

Journal of Neurophysiology ◽

10.1152/jn.00941.2012 ◽

2014 ◽

Vol 111 (6) ◽

pp. 1259-1273 ◽

Cited By ~ 13

Author(s):

Jossina Gonzalez ◽

Isaiah S. Morales ◽

Desiree M. Villarreal ◽

Brian E. Derrick

Keyword(s):

Nmda Receptor ◽

Low Frequency ◽

Perforant Path ◽

Paired Pulse ◽

Anesthetized Rats ◽

Low Frequency Stimulation ◽

Frequency Stimulation ◽

Slow Onset

The expression of homosynaptic long-term depression (LTD) is thought to mediate a crucial role in sustaining memory function. Our in vivo investigations of LTD expression at lateral (LPP) and medial perforant path (MPP) synapses in the dentate gyrus (DG) corroborate prior demonstrations that PP-DG LTD is difficult to induce in intact animals. In freely moving animals, LTD expression occurred inconsistently among LPP-DG and MPP-DG responses. Interestingly, following acute electrode implantation in anesthetized rats, low-frequency stimulation (LFS; 900 pulses, 1 Hz) promotes slow-onset LTP at both MPP-DG and LPP-DG synapses that utilize distinct induction mechanisms. Systemic administration of the N-methyl-d-aspartate (NMDA) receptor antagonist (+/−)-cyclopiperidine-6-piperiperenzine (CPP; 10 mg/kg) 90 min before LFS selectively blocked MPP-DG but not LPP-DG slow onset LTP, suggesting MPP-DG synapses express a NMDA receptor-dependent slow onset LTP whereas LPP-DG slow onset LTP induction is NMDA receptor independent. In experiments where paired-pulse LFS (900 paired pulses, 200-ms paired-pulse interval) was used to induce LTD, paired-pulse LFS of the LPP resulted in rapid onset LTP of DG responses, whereas paired-pulse LFS of the MPP induced slow onset LTP of DG responses. Although LTD observations were very rare following acute electrode implantation in anesthetized rats, LPP-DG LTD was demonstrated in some anesthetized rats with previously implanted electrodes. Together, our data indicate in vivo PP-DG LTD expression is an inconsistent phenomenon that is primarily observed in recovered animals, suggesting perturbation of the dentate through surgery-related tissue trauma influences both LTD incidence and LTP induction at PP-DG synapses in vivo.

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BDNF controls bidirectional endocannabinoid-plasticity at corticostriatal synapses

10.1101/550947 ◽

2019 ◽

Author(s):

Giuseppe Gangarossa ◽

Sylvie Perez ◽

Yulia Dembitskaya ◽

Ilya Prokin ◽

Hugues Berry ◽

...

Keyword(s):

Low Frequency ◽

Dorsal Striatum ◽

Brain Structures ◽

Spike Timing ◽

Procedural Learning ◽

Two Photon ◽

Low Frequency Stimulation ◽

Frequency Stimulation ◽

Corticostriatal Plasticity

ABSTRACTThe dorsal striatum exhibits bidirectional corticostriatal synaptic plasticity, NMDAR- and endocannabinoids-(eCB)-mediated, necessary for the encoding of procedural learning. Therefore, characterizing factors controlling corticostriatal plasticity is of crucial importance. Brain-derived neurotrophic factor (BDNF) and its receptor, the tropomyosine receptor kinase-B (TrkB), shape striatal functions and their dysfunction deeply affect basal ganglia. BDNF/TrkB signaling controls NMDAR-plasticity in various brain structures including striatum. However, despite cross-talks between BDNF and eCBs, the role of BDNF in eCB-plasticity remains unknown. Here, we show that BDNF/TrkB signaling promotes eCB-plasticity (LTD and LTP) induced by rate-based (low-frequency stimulation) or spike-timing-based (spike-timing-dependent plasticity, STDP) paradigm in striatum. We show that TrkB activation is required for the expression and the scaling of both eCB-LTD and eCB-LTP. Using two-photon imaging of the dendritic spines combined with patch-clamp recordings, we show that TrkB activation induces an intracellular calcium boost, thus increasing eCB synthesis and release. We provide a mathematical model for the dynamics of the signaling pathways involved in corticostriatal plasticity. Finally, we show that TrkB activation allows an enlargement of the domain of expression of eCB-STDP. Our results reveal a novel role for BDNF/TrkB signaling in governing eCB-plasticity expression in striatum, and thus the engram of procedural learning.

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Effects of Ethanol on Synaptic Plasticity and NMDA Currents in the Juvenile Rat Dentate Gyrus

Brain Plasticity ◽

10.3233/bpl-200110 ◽

2020 ◽

Vol 6 (1) ◽

pp. 123-136 ◽

Cited By ~ 1

Author(s):

Scott D. Sawchuk ◽

Hannah M.O. Reid ◽

Katie J. Neale ◽

James Shin ◽

Brian R. Christie

Keyword(s):

Dentate Gyrus ◽

Hippocampal Slices ◽

Age Groups ◽

Low Frequency ◽

Nmda Antagonist ◽

Perforant Path ◽

Whole Cell ◽

Low Frequency Stimulation ◽

Acute Ethanol ◽

Frequency Stimulation

Background and Objectives: We examined how acute ethanol (EtOH) exposure affects long term depression (LTD) in the dentate gyrus (DG) of the hippocampus in juvenile rats. EtOH is thought to directly modulate n-methyl-D-aspartate receptor (NMDAr) currents, which are believed important for LTD induction. LTD in turn is believed to play an important developmental role in the hippocampus by facilitating synaptic pruning. Methods: Hippocampal slices (350μm) were obtained at post-natal day (PND) 14, 21, or 28. Field EPSPs (excitatory post-synaptic potential) or whole-cell EPSCs (excitatory post-synaptic conductance) were recorded from the DG (dentate gyrus) in response to medial perforant path activation. Low-frequency stimulation (LFS; 900 pulses; 120 s pulse) was used to induce LTD. Results: Whole-cell recordings indicated that EtOH exposure at 50mM did not significantly impact ensemble NMDAr EPSCs in slices obtained from animals in the PND14 or 21 groups, but it reliably produced a modest inhibition in the PND28 group. Increasing the concentration to 100 mM resulted in a modest inhibition of NMDAr EPSCs in all three groups. LTD induction and maintenance was equivalent in magnitude in all three age groups in control conditions, however, and surprisingly, NMDA antagonist AP5 only reliably blocked LTD in the PND21 and 28 age groups. The application of 50 mM EtOH attenuated LTD in all three age groups, however increasing the concentration to 100 mM did not reliably inhibit LTD. Conclusions: These results indicate that the effect of EtOH on NMDAr-EPSCs recorded from DGCs is both age and concentration dependent in juveniles. Low concentrations of EtOH can attenuate, but did not block LTD in the DG. The effects of EtOH on LTD do not align well with it’s effects on NNMDA receptors.

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