We have shown that some neural activity is required for the maintenance of long-term potentiation (LTP) at visual cortical inhibitory synapses. We tested whether this was also the case in N-methyl-d-aspartate (NMDA) receptor-independent LTP of excitatory connections in layer 2/3 cells of developing rat visual cortex. This LTP occurred after 2-Hz stimulation was applied for 15 min and always persisted for several hours while test stimulation was continued at 0.1 Hz. When test stimulation was stopped for 1 h after LTP induction, only one-third of the LTP instances disappeared, but most did disappear under a pharmacological suppression of spontaneous firing, indicating that LTP maintenance requires either evoked or spontaneous activities. LTP was totally abolished by a temporary blockade of action potentials with lidocaine or the removal of extracellular Ca(2+) after LTP induction, but it persisted under a voltage clamp of postsynaptic cells or after a temporary blockade of postsynaptic activity with the glutamate receptor antagonist kynurenate, suggesting that LTP maintenance requires presynaptic, but not postsynaptic, firing and Ca(2+) entry. More than one-half of the LTP instances were abolished after a pharmacological blockade of P-type Ca(2+) channels, whereas it persisted after either L-type or Ni(2+)-sensitive Ca(2+) channel blockades. These results show that the maintenance of NMDA receptor-independent excitatory LTP requires presynaptic firing and Ca(2+) channel activation as inhibitory LTP, although the necessary level of firing and Ca(2+) entry seems lower for the former than the latter and the Ca(2+) channel types involved are only partly the same.
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http://dx.doi.org/10.1152/jn.00602.2003 | DOI Listing |
Free Radic Res
December 2024
Department of Pathology and Biological Responses, Nagoya University Graduate School of Medicine, 65 Tsurumai-cho, Showa-ku, Nagoya 466-8550, Japan.
Plasma, which was coined by Irving Langmuir in 1928, is the fourth physical state after the solid/liquid/gas phases. Low-temperature plasma (LTP) is a contradictory condition that involves high energy with free radicals at near-body temperatures and was developed through engineering in the 1990's. Research on LTP in engineering and medical fields has rapidly developed since the 2000's.
View Article and Find Full Text PDFPlant Mol Biol
December 2024
State Key Laboratory of Crop Genetics & Germplasm Enhancement and Utilization, Zhongshan Biological Breeding laboratoryr, Nanjing Agricultural University, Nanjing, 210095, China.
Adv Mater
December 2024
Department of Electrical and Computer Engineering, The University of Texas at Austin, Austin, TX, 78712, USA.
A synaptic memristor using 2D ferroelectric junctions is a promising candidate for future neuromorphic computing with ultra-low power consumption, parallel computing, and adaptive scalable computing technologies. However, its utilization is restricted due to the limited operational voltage memory window and low on/off current (I) ratio of the memristor devices. Here, it is demonstrated that synaptic operations of 2D InSe ferroelectric junctions in a planar memristor architecture can reach a voltage memory window as high as 16 V (±8 V) and I ratio of 10, significantly higher than the current literature values.
View Article and Find Full Text PDFJ Hazard Mater
December 2024
Department of Pharmacology & Toxicology, University of Texas Medical Branch, Galveston, TX 77555, USA; Center for Precision Environmental Health, Baylor College of Medicine, Houston, TX 77030, USA. Electronic address:
Environmental exposure to pesticides at levels deemed safe by regulatory agencies has been linked to increased risk for neurodevelopmental disorders. Yet, the mechanisms linking exposure to these disorders remain unclear. Here, we show that maternal exposure to the pesticide deltamethrin (DM) at the no observed adverse effect level (NOAEL) disrupts long-term potentiation (LTP) in the hippocampus of adult male offspring three months after exposure, a phenotype absent in female offspring.
View Article and Find Full Text PDFJ Allergy Clin Immunol Pract
December 2024
EUCAN Medical Affairs, Takeda Pharmaceuticals International AG, Glattpark-Opfikon (Zürich), Switzerland.
Background: Hereditary angioedema (HAE) is a rare genetic disease characterized by recurrent episodes of cutaneous or subcutaneous edema. There is clinical need for treatments that reduce the rate of HAE attacks in patients.
Objectives: Primary objectives were to evaluate the effectiveness of lanadelumab on attack free rate (AFR; proportion of patients who had zero HAE attacks), and on every two weeks (Q2W) and every four weeks (Q4W) adjustments on AFR.
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