Main characteristics of insulin signalling in neurons, astrocytes, microglia and the vascular system. AMPA, α-amino-3-hydroxy-5-methyl-4-isoxazole propionic acid; BBB, blood–brain barrier; GLUT, glucose transporter type protein; IR, insulin receptor; IRS, insulin receptor substrate; LTD, long-term depression; LTP, long-term potentiation; NMDA, N-methyl-d-aspartate; NO, nitric oxide.