Rat Agrin is a large proteoglycan secreted by motor neurons, muscle cells, and others, and serves as a key component of the extracellular matrix. As the central organizer of neuromuscular junction formation, it efficiently clusters acetylcholine receptors on the postsynaptic membrane by binding to the LRP4/MuSK receptor complex, thereby driving the development and maturation of neuromuscular synapses. Beyond the nervous system, Agrin is also involved in regulating myotube formation, cardiac regeneration, and stem cell differentiation. Studies have shown that exogenous Agrin protein can promote axonal regeneration after spinal cord injury and induce dedifferentiation and proliferation of cardiomyocytes, demonstrating strong tissue repair potential. Consequently, Agrin has emerged as a highly promising therapeutic protein molecule in the fields of neural and cardiac regeneration.