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In this website I cover the topic of neuronal survival; including an overview of cell death, molecules and mechanisms involved in maintaining neurons and why tight regulation of these mechanisms is so important.
A huge amount of neurons grow during developent and between 20 and 80% of these will die during development depending on the area of the brain they they are in. Many systems are in place to make sure that the right type of neuron is in the right place, that it makes the correct connections and that the number of input neurons matches up to the number of connections that the post-synaptic structure requires. Should any neuron not conform to these requirements it is induced to undergo cell death by apoptosis.
Neurons that do conform to these requirements receive survival signals known as trophic factors which keep the neuron alive.
Further methods are required to maintain neurons once development has finished.
Banner image from Flickr: www.flickr.com/photos/lorelei-ranveig/2294885580/ under Creative Commons Licence 2.0, credited to Dr Jonathan Clarke. Wellcome Images. images.wellcome.ac.uk/
Image from Wellcome Images https://images.wellcome.ac.uk/, image reference: B0001894, :author: Julie Reza, licence: Creative Commons Attribution-Non-Commercial version 2.0
Image from Wikimedia Commons, https://commons.wikimedia.org/wiki/File:Pyramidal_hippocampal_neuron_40x.jpg, author: MethoxyRoxy, licence: CreativeCommons Attribution-ShareAlike 2.5