Search results for "Axon hillock"
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Synaptic Phospholipid Signaling Modulates Axon Outgrowth via Glutamate-dependent Ca2+-mediated Molecular Pathways.
2015
Abstract Altered synaptic bioactive lipid signaling has been recently shown to augment neuronal excitation in the hippocampus of adult animals by activation of presynaptic LPA2-receptors leading to increased presynaptic glutamate release. Here, we show that this results in higher postsynaptic Ca2+ levels and in premature onset of spontaneous neuronal activity in the developing entorhinal cortex. Interestingly, increased synchronized neuronal activity led to reduced axon growth velocity of entorhinal neurons which project via the perforant path to the hippocampus. This was due to Ca2+-dependent molecular signaling to the axon affecting stabilization of the actin cytoskeleton. The spontaneous…
Origin of impulse initiation in the slowly adapting stretch receptor of the crayfish
1974
Characteristic for the crayfish stretch receptor is a gradual decrease in axon diameter up to a stretch of axon about 350 μm away from the soma-axon border. In response to depolarizing currents applied at different positions along the axon this stretch of axon can be localized as the most excitable membrane region. When depolarizing current steps of 10–25 nA intensity are injected into the soma the first impulse is always triggered in the soma (due to sudden rise in the membrane potential) while the second impulse originates at the axon region of highest escitability. As the intensity of the stimulus is increased the site of impulse initiation along the axon shifts nearer to the receptor so…