PLAT and schizophrenia: Activation of NMDA receptors, reelin and neurotrophins, as well as dopamine release are some of the many neuroprotective mechanisms mediated by tPA or by plasmin that are defective in schizophrenia.12, 14, 15, 16, 17, 18, 19, 20, 21 The NMDA receptor stimulates neuronal migration and is involved in mechanisms of synaptic plasticity, a prerequisite for learning and memory skills.