Long-term potentiation (LTP) is considered a cellular correlate of learning and memory. The presence of G protein-activated inwardly rectifying K(+) (GIRK) channels near excitatory synapses on dendritic spines suggests their possible involvement in synaptic plasticity. However, whether activity-dependent regulation of channels affects excitatory synaptic plasticity is unknown. In a companion article we have reported activity-dependent regulation of GIRK channel density in cultured hippocampal neurons that requires activity oF receptors (NMDAR) and protein phosphatase-1 (PP1) and takes place within 15 min. In this study, we performed whole-cell recordings of cultured hippocampal neurons and found that NMDAR activation increases basal GIRK current and GIRK channel activation mediated by adenosine A(1) receptors, but not GABA(B) receptors. Given the similar involvement of NMDARs, adenosine receptors, and PP1 in depotentiation of LTP caused by low-frequency stimulation that immediately follows LTP-inducing high-frequency stimulation, we wondered whether NMDAR-induced increase in GIRK channel surface density and current may contribute to the molecular mechanisms underlying this specific depotentiation. Remarkably, GIRK2 null mutation or GIRK channel blockade abolishes depotentiation of LTP, demonstrating that GIRK channels are critical for depotentiation, one form of excitatory synaptic plasticity.
Learn more about receptors here:
brainly.com/question/11985070
#SPJ4
The strongest component of the cell wall<span> is a carbohydrate called cellulose, a polymer of glucose. The </span>cell wall gives rigidity<span> and strength to the </span>plant cells<span> which offers protection against mechanical stress. ... The </span>rigidity<span> of primary </span>plant<span> tissues is due to turgor pressure and not from rigid </span>cell walls<span>.</span>
In the matrix of mitochondria the reactions known as the citric acid or Krebs cycle produce a chemical called NADH. NADH is then used by enzymes embedded in the mitochondrial inner membrane to generate adenosine triphosphate (ATP). In ATP the energy is stored in the form of chemical bonds.
Only the talus bone articulates with the leg bones.