Na(+)/K(+)- and Mg(2+)-ATPases and Their Interaction with AMPA, NMDA and D(2) Dopamine Receptors in an Animal Model of Febrile Seizures

Febrile seizures (FS) are one of the most common seizure disorders in childhood which are classified into short and prolonged, depending on their duration. Short FS are usually considered as benign. However, epidemiological studies have shown an association between prolonged FS and temporal lobe epilepsy. The development of animal models of FS has been very useful to investigate the mechanisms and the consequences of FS. One of the most used, the “hair dryer model”, has revealed that prolonged FS may lead to temporal lobe epilepsy by altering neuronal function. Several pieces of evidence suggest that Na(+)/ K(+)-ATPase and Mg(2+)-ATPase may play a role in this epileptogenic process. In this work, we found that hyperthermia-induced seizures (HIS) significantly increased the activity of Na(+)/ K(+)-ATPase and Mg(2+)-ATPase five and twenty days after hyperthermic insult, respectively. These effects were diminished in response to AMPA, D(2) dopamine A(1) and A(2A) receptors activation, respectively. Furthermore, HIS also significantly increased the protein level of the AMPA subunit GluR1. Altogether, the increased Na(+)/ K(+)-ATPase and Mg(2+)-ATPase agree well with the presence of protective mechanisms. However, the reduction in ATPase activities in the presence of NMDA and AMPA suggest an increased propensity for epileptic events in adults.