scholarly journals Stimulation of raphe (obscurus) nucleus causes long-term potentiation of phrenic nerve activity in cat.

1986 ◽  
Vol 381 (1) ◽  
pp. 169-179 ◽  
Author(s):  
D E Millhorn
Keyword(s):  
Phrenic Nerve ◽  
Long Term Potentiation ◽  
Nerve Activity ◽  
Phrenic Nerve Activity ◽  
Term Potentiation ◽  
Stimulation Of

Induction of long-term potentiation without participation of N-methyl-D-aspartate receptors in kitten visual cortex

1991 ◽  
Vol 65 (1) ◽  
pp. 20-32 ◽  
Author(s):  
Y. Komatsu ◽  
S. Nakajima ◽  
K. Toyama
Keyword(s):  
Nmda Receptors ◽  
Stimulus Frequency ◽  
Low Frequency ◽  
Nmda Antagonist ◽  
Long Term Potentiation ◽  
Conditioning Stimulation ◽  
Postsynaptic Potential ◽  
Term Potentiation ◽  
Stimulation Of

1. Intracellular recording was made from layer II-III cells in slice preparations of kitten (30-40 days old) visual cortex. Low-frequency (0.1 Hz) stimulation of white matter (WM) usually evoked an excitatory postsynaptic potential (EPSP) followed by an inhibitory postsynaptic potential (IPSP). The postsynaptic potentials (PSPs) showed strong dependence on stimulus frequency. Early component of EPSP and IPSP evoked by weak stimulation both decreased monotonically at frequencies greater than 0.5-1 Hz. Strong stimulation similarly depressed the early EPSP at higher frequencies (greater than 2 Hz) and replaced the IPSP with a late EPSP, which had a maximum amplitude in the stimulus frequency range of 2-5 Hz. 2. Very weak WM stimulation sometimes evoked EPSPs in isolation from IPSPs. The falling phase of the EPSP revealed voltage dependence characteristic to the responses mediated by N-methyl-D-aspartate (NMDA) receptors and was depressed by application of an NMDA antagonist DL-2-amino-5-phosphonovalerate (APV), whereas the rising phase of the EPSP was insensitive to APV. 3. The early EPSPs followed by IPSPs were insensitive to APV but were replaced with a slow depolarizing potential by application of a non-NMDA antagonist 6,7-dinitro-quinoxaline-2,3-dione (DNQX), indicating that the early EPSP is mediated by non-NMDA receptors. The slow depolarization was mediated by NMDA receptors because it was depressed by membrane hyperpolarization or addition of APV. 4. The late EPSP evoked by higher-frequency stimulation was abolished by APV, indicating that it is mediated by NMDA receptors, which are located either on the recorded cell or on presynaptic cells to the recorded cells. 5. Long-term potentiation (LTP) of EPSPs was examined in cells perfused with solutions containing 1 microM bicuculline methiodide (BIM), a gamma-aminobutyric acid (GABA) antagonist. WM was stimulated at 2 Hz for 15 min as a conditioning stimulus to induce LTP, and the resultant changes were tested by low-frequency (0.1 Hz) stimulation of WM. 6. LTP of early EPSPs occurred in more than one-half of the cells (8/13) after strong conditioning stimulation. The rising slope of the EPSP was increased 1.6 times on average. 7. To test involvement of NMDA receptors in the induction of LTP in the early EPSP, the effect of conditioning stimulation was studied in a solution containing 100 microM APV, which was sufficient to block completely synaptic transmission mediated by NMDA receptors. LTP occurred in the same frequency and magnitude as in control solution.

On the Respective Roles of Nitric Oxide and Carbon Monoxide in Long-Term Potentiation in the Hippocampus

1999 ◽  
Vol 6 (1) ◽  
pp. 63-76 ◽  
Author(s):  
Min Zhuo ◽  
Jarmo T. Laitinen ◽  
Xiao-Ching Li ◽  
Robert D. Hawkins
Keyword(s):  
Nitric Oxide ◽  
Carbon Monoxide ◽  
Heme Oxygenase ◽  
Guanylyl Cyclase ◽  
Hippocampal Slices ◽  
Long Term Potentiation ◽  
No Synthase ◽  
Term Potentiation ◽  
Stimulation Of

Perfusion of hippocampal slices with an inhibitor nitric oxide (NO) synthase blocked induction of long-term potentiation (LTP) produced by a one-train tetanus and significantly reduced LTP by a two-train tetanus, but only slightly reduced LTP by a four-train tetanus. Inhibitors of heme oxygenase, the synthetic enzyme for carbon monoxide (CO), significantly reduced LTP by either a two-train or four-train tetanus. These results suggest that NO and CO are both involved in LTP but may play somewhat different roles. One possibility is that NO serves a phasic, signaling role, whereas CO provides tonic, background stimulation. Another possibility is that NO and CO are phasically activated under somewhat different circumstances, perhaps involving different receptors and second messengers. Because NO is known to be activated by stimulation of NMDA receptors during tetanus, we investigated the possibility that CO might be activated by stimulation of metabotropic glutamate receptors (mGluRs). Consistent with this idea, long-lasting potentiation by the mGluR agonist tACPD was blocked by inhibitors of heme oxygenase but not NO synthase. Potentiation by tACPD was also blocked by inhibitors of soluble guanylyl cyclase (a target of both NO and CO) or cGMP-dependent protein kinase, and guanylyl cyclase was activated by tACPD in hippocampal slices. However, biochemical assays indicate that whereas heme oxygenase is constitutively active in hippocampus, it does not appear to be stimulated by either tetanus or tACPD. These results are most consistent with the possibility that constitutive (tonic) rather than stimulated (phasic) heme oxygenase activity is necessary for potentiation by tetanus or tACPD, and suggest that mGluR activation stimulates guanylyl cyclase phasically through some other pathway.

Type I adenylyl cyclase functions as a coincidence detector for control of cyclic AMP response element-mediated transcription: synergistic regulation of transcription by Ca2+ and isoproterenol

1994 ◽  
Vol 14 (12) ◽  
pp. 8272-8281
Author(s):  
S Impey ◽  
G Wayman ◽  
Z Wu ◽  
D R Storm
Keyword(s):  
Cyclic Amp ◽  
Adenylyl Cyclase ◽  
Long Term Potentiation ◽  
Regulation Of Transcription ◽  
Type I ◽  
Hek 293 ◽  
293 Cells ◽  
Term Potentiation ◽  
Stimulation Of

Studies carried out with mammals and invertebrates suggest that Ca(2+)-sensitive adenylyl cyclases may be important for neuroplasticity. Long-term potentiation in the hippocampus requires increases in intracellular Ca2+ which are accompanied by elevated cyclic AMP (cAMP). Furthermore, activation of cAMP-dependent protein kinase is required for the late stage of long-term potentiation in the CA1 region of the hippocampus, which is also sensitive to inhibitors of transcription. Therefore, some forms of synaptic plasticity may require coordinate regulation of transcription by Ca2+ and cAMP. In this study, we demonstrate that the expression of type I adenylyl cyclase in HEK-293 cells allows Ca2+ to stimulate reporter gene activity mediated through the cAMP response element. Furthermore, simultaneous activation by Ca2+ and isoproterenol caused synergistic stimulation of transcription in HEK-293 cells and cultured neurons. We propose that Ca2+ and neurotransmitter stimulation of type I adenylyl cyclase may play a role in synaptic plasticity by generating optimal cAMP signals for regulation of transcription.

Reversal of long-term potentiation (depotentiation) induced by tetanus stimulation of the input to CA1 neurons of guinea pig hippocampal slices

1991 ◽  
Vol 555 (1) ◽  
pp. 112-122 ◽  
Author(s):  
Satoshi Fujii ◽  
Kazuo Saito ◽  
Hiroyoshi Miyakawa ◽  
Ken-ichi Ito ◽  
Hiroshi Kato
Keyword(s):  
Guinea Pig ◽  
Hippocampal Slices ◽  
Long Term Potentiation ◽  
Ca1 Neurons ◽  
Term Potentiation ◽  
Stimulation Of

Time-dependent phrenic nerve responses to carotid afferent activation: intact vs. decerebellate rats

1993 ◽  
Vol 265 (4) ◽  
pp. R811-R819 ◽  
Author(s):  
F. Hayashi ◽  
S. K. Coles ◽  
K. B. Bach ◽  
G. S. Mitchell ◽  
D. R. McCrimmon
Keyword(s):  
Phrenic Nerve ◽  
Carotid Sinus ◽  
Carotid Sinus Nerve ◽  
Short Term ◽  
Nerve Activity ◽  
A Value ◽  
Afferent Activation ◽  
Term Potentiation ◽  
Long Term Facilitation

The objectives were to determine 1) respiratory responses to carotid chemoreceptor inputs in anesthetized rats and 2) whether the cerebellar vermis plays a role in these responses. A carotid sinus nerve was stimulated (20 Hz) with five 2-min trains, each separated by approximately 3 min. During stimulation, respiratory frequency (f), peak amplitude of integrated phrenic nerve activity (integral of Phr), and their product (f x integral of Phr) immediately increased. As stimulation continued, integral of Phr progressively increased to a plateau [short-term potentiation (STP)], but f and f x integral of Phr decreased [short-term depression (STD)] to a value still above control. Upon stimulus termination, integral of Phr progressively decreased but remained above control; f and f x integral of Phr transiently decreased below baseline. After the final stimulation, integral of Phr remained above control for at least 30 min [long-term facilitation (LTF)]. Repeated 5-min episodes of isocapnic hypoxia also elicited STP, STD, and LTF. Vermalectomy lowered the CO2-apneic threshold and eliminated LTF. In conclusion, carotid chemoreceptor activation in rats elicits STP and LTF similar to that in cats; the vermis may play a role in LTF. A new response, STD, was observed.

Theta-burst stimulation of primary afferents drives long-term potentiation in the spinal cord and persistent pain via α2δ-1–bound NMDA receptors

2021 ◽  
pp. JN-RM-1968-21
Author(s):  
Yuying Huang (黄玉莹) ◽  
Shao-Rui Chen (陈少瑞) ◽  
Hong Chen (陈红) ◽  
Jing-Jing Zhou (周京京) ◽  
Daozhong Jin (金道忠) ◽  
...  
Keyword(s):  
Spinal Cord ◽  
Nmda Receptors ◽  
Long Term Potentiation ◽  
Primary Afferents ◽  
Theta Burst Stimulation ◽  
Burst Stimulation ◽  
Term Potentiation ◽  
Theta Burst ◽  
Stimulation Of
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