Assessment of genes involved in behavior, learning, memory, and synaptic plasticity following status epilepticus in rats.

Objective: In this study, it was aimed to evaluate cognitive and behavioral changes after status epilepticus (SE) induced by pentylenetetrazole in immature rats via Morris water maze and open-field area tests and to assess alterations in expression of 84 key genes involved in synaptic plasticity after SE.

Method: The study was conducted on 30 immature rats (12-days old). The rats were assigned into groups as control and experiment (SE) groups. The SE was induced by pentylenetetrazole in 12-days old rats. In addition, experiment group was divided into two groups as mature (n = 8) and immature SE (n = 8) subgroups. Again, the control group was divided into two groups as mature (n = 7) and immature control (n = 7) subgroups. Hippocampal tissue samples were prepared, and expression of 84 key genes involved in synaptic plasticity was assessed in Genome and Stem Cell Center of Erciyes University before behavioral tests in immature rats (22-days old) and after open-filed area and Morris water maze tests in mature rats (72-days old) in both experiment and control groups.

Results: No significant difference was detected in behavioral tests assessing spatial memory and learning among groups. Significant differences were detected, ARC (activity-regulated cytoskeleton-associated protein), BDNF (brain-derived neurotrophic factor), MAPK1 (mitogen-activated protein kinase 1), NR4A1 (nuclear receptor subfamily 4 group A member 1), PPP3CA (protein phosphatase 3 catalytic subunit alpha), RGS2 (regulator of G protein signaling 2), and TNF (tumor necrosis factor) gene expressions between control and experiment groups in immature rats whereas in ADCY8 (adenylate cyclase 8), BDNF (brain-derived neurotrophic factor), EGR4 (early growth response 4), and KIF17 (kinesin family member 17) gene expressions between control and experiment groups in mature rats.

Discussion: In this study, differences detected in gene expressions of synaptic plasticity after SE indicate in which steps of synaptic plasticity may be problematic in epileptogenesis. The gene expressions in this study may be considered as potential biomarkers; however, epileptogenesis is a dynamic process and cannot be explained through a single mechanism. Future studies on epileptogenesis and studies specifically designed to evaluate genes detected in our study will further elucidate synaptic plasticity in epilepsy and epileptogenesis.