This lecture covers the cellular mechanisms underlying neurotransmitter release in the brain. It discusses the role of voltage-gated calcium channels in triggering exocytosis of synaptic vesicles, the calcium-evoked release rate, and the molecular mechanisms involving proteins like synaptotagmin and syntaxin. Additionally, it explores the synaptic vesicle cycle, including vesicle docking, recycling, and the key players in neurotransmitter release. Overall, the lecture provides a detailed insight into the complex process of neurotransmitter release at the synaptic cleft.