NEUR30004 Lecture Notes - Lecture 23: Hygiene Hypothesis, Rodent, Oligodendrocyte Progenitor Cell
11 Aug 2018
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* myelin is quite dynamic and very important in the adult setting as well as the development setting. * myelin is produced by two different types of cells. In the cns it is produced by oligodendrocytes a(cid:374)d i(cid:374) the pns it"s p(cid:396)odu(cid:272)ed (cid:271)(cid:455) s(cid:272)h(cid:449)a(cid:374)(cid:374) (cid:272)ells. These cells both surround/in sheath axons in this fatty membrane called myelin. * in the cns, an oligodendrocyte can be seen via em and the oligodendrocyte is sending out a p(cid:396)o(cid:272)ess a(cid:374)d (cid:373)(cid:455)eli(cid:374)ati(cid:374)g a(cid:374) a(cid:454)o(cid:374) a(cid:374)d it"s also se(cid:374)di(cid:374)g out a(cid:374)othe(cid:396) a(cid:454)o(cid:374) that"s (cid:373)(cid:455)eli(cid:374)ati(cid:374)g a(cid:374)othe(cid:396) axon. So, within the cns, a single oligodendrocyte can myelinate up to 50 axons and so they can be quite large and as a consequence of the wrapping they generate a huge amount of membrane. * within the nodes of ranvier are sodium channel which allows conductance to occur. * in an unmyelinated axon where the propagation of the action potential projects by successive depolarisation of the sodium channels.
