![]() Simpler morphology (for review, see Hogan 1999). Such as trachea or blood vessels, for those tubular structures are formed by the collaboration of multiple cells, each with To have some unique features and differ substantially from those regulating the formation of other highly branched structures The cellular mechanisms controlling the formation of these elaborate cellular structures are likely For example, a Purkinje cell in the cerebellum can elaborate remarkably complex yet In this review, we will first consider the functional implications of dendritic branching patterns and then discuss dendriteįormation and possible commonality between dendrite development and synaptic plasticity.įrom the cell biological point of view, the elaborate and stereotyped dendritic branching of a neuron is a striking example ![]() Input received by a neuron ( Stuart et al. The dendriticīranching pattern varies to a great extent with the neuronal type, and is an important determinant of the synaptic or sensory Regardless of whether they receive sensory or synaptic input, the dendrites are the antennae of the neurons. These sensory stimuli induce receptor potentials in the dendrite, analogous to the synaptic potentials generatedĪt the synapse ( Hille 2001). Of many sensory neurons are sensory endings that transduce signals from the external environment, such as mechanical or chemical It is worth noting that not all dendrites receive synaptic input. Most likely, synapse formation involves two-way communications between the presynapticĬell and the postsynaptic cell. Just passive participants in this process. To make synapses with the correct targets, which are usually the dendrites of the postsynaptic neurons. The axon of a presynaptic neuron needs to be properly guided Synapse formation involves two partners, axons and dendrites. San Francisco, California 94143-0725, USA Howard Hughes Medical Institute, Departments of Physiology, Biochemistry, and Biophysics, University of California, San Francisco,.Základy neurověd v zubním lékařství . MEFANET, ©2011. The last revision , . . local (interneurons) - connect nearby areas.Principal (projection) - they connect distant areas of the nervous system.Golgi type II - neurons with short neurites.Golgi type I - neurons with long neurites.pseudounipolar (has a long dendrite that merges with the axon).bipolar (contains one relatively long dendrite and axon, sensory neurons (skin, auditory, olfactory) and nociceptive fibres).multipolar (containing many small, richly branching dendrites).Neurons can be divided morphologically, according to the length of the axon and functionally. We distinguish between anterograde transport (from the cell body) and retrograde transport (into the cell body - spread of viruses and toxins).Ĥ. The main function of the neurite is the transport of certain substances from the body to the telodendrites, which is dependent on a developed system of neurofilaments and neurotubules. In the PNS, the extracellular space at the site of the Ranvier notch is separated from the surroundings by a continuous basement membrane that bridges over the notch area in the CNS, astrocyte processes are directly seated there. The speed of conduction is directly proportional to the length of the internodes. Throughout, the myelin sheath is interrupted by Ranvier notches, with the sections between each notch called internodes. It is important for the transmission of excitement, the thicker the axon, the faster the transmission. The myelinated section occurs along the entire length of the axon except for its beginning and terminal branching. ![]() The site of neurite outgrowth is the axon bump this, together with the initial segment of the neurite, is the site of action potential generation. Neurochemically, they are rich in voltage-gated ion channels. They contain ribosomes, a small number of mitochondria and neurotubules. Neurites are long processes leading excitations from the body of the neuron (to the next neuron or effector), i.e.
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