Acetylcholine (ChA) is a classical neurotransmitter, which is mainly located in neuromuscular junctions, where this chemical stimulates motor neurons to active muscles, in synapses and other sites across the central nervous system. Cholinergic neurons are the cells that uses acetylcholine to send its messages and perform other important functions [22].
Acetylcholine is synthesized in neuronal terminals from acetyl CoA and choline, the enzymes of this reaction is choline acetyltransferase (ChAT). The concentration of choline in plasma is about 10mM, from here it is taken up by cholinergic neurons through Na+/Choline transporter [Fig.6.] [22]. ChAT is an enzyme that synthesizes ChA and stores it in vesicles until the …show more content…
Astrocyte roles in Alzheimer’s Disease (AD)
Alzheimer is a neurodegenerative diseases caused by the formation of amyloid- plaques, where A peptides clumpse together, that interupt the normal functioning of neurons. This results in loss of memory, changes in thinking and behaviour. The symptoms of alzheimer’s disease develop over the time [25]. A is a peptided formed from 42 different amino acids produced by amyloid precursor protein (APP).
It is well known that astrocytes have an impact on progression of Alzheimer’s disease. As some studies suggest, reactive astrocytes surround the formed plaques and undergo astrogliosis, where active astrocytes store large amounts of A, when in other brain tissues astroglial cells endure gradual loss of effectivness, which results in changes of synaptic plasticity and deterioration specific to Alzheimer [26]. Astrocytes are the cells, which degrade the amyloid- plaques and this happens during the astrocytic hypertorphic processes, therefore the deposit formation of the A in extracellular fluid is inhibited. Yet, it is not fully understood, how astrocytes manage to indetify and degrade amyloid-, but it is suggested that apolipo-protein E (ApoE), which is secreted by astrocytes, is responsible for this cellular process [27]. Besides that, asotryctes perform protective functions by suppressing activated microglia in