Astrocyte calcium wave induces seizure-like behavior in neuron network

It has been revealed experimentally that astrocytes can participate in synaptic transmission by modulating and responding to the release of neurotransmitters with calcium elevations. Researches suggest that seizure-like discharges (SDs) or seizure-like firings (SFs) in neurons, characterizing neurological disorder, may arise locally in restricted areas (focal area) and then propagate throughout the brain. But the underlying mechanism remains unclear. To study the possible role astrocytes playing in the SDs propagation, we construct a minimal neuron-astrocyte network model by connecting a neurons chain and an astrocytes chain. The focal area is modelled by an IP3 reservoir which provides persistent IP3 out-flux. The study suggests that calcium wave propagation in astrocytes determines the propagation of SDs in the connected neurons. On the other hand, SDs in neurons allows the calcium wave propagates longer distance in the astrocytes, which suggests the mutually cooperating of astrocytes and neurons in accomplishing SD propagation. Furthermore, once SDs propagate and occupy the neuron network, it could not be terminated by recovery of the focal area. The results may imply that treatment of brain disorders should not only focus on local area but the whole neuron network.