Neuroglial cells are drawing attention from the community due to technical advances. Traditionally, neuroglial cells play a supporting role in the neural systems. In the last decade, modulations in computations due to neuroglial cells were unveiled in different experiments. Astrocytes, star-shaped neuroglial cells, are known to involve processes of neurotransmitters. Recently, I have jointly reported that blockages of astrocytic NMDA receptors can modulate the distribution of release probabilities of neurotransmitters. By incorporating this discovery into an existing computational model, we found that this modulation in the release probability of neurotransmitters can degrade long-term plasticity. This result will be curial to understanding the role of astrocytes in neural computations and impairments linked to dysfunctions of astrocytes.