Pentylenetetrazole-induced seizures cause impairment of memory acquisition and consolidation in zebrafish (Danio rerio)

Epilepsy is characterized by the occurrence of seizures, and the high prevalence of epilepsy-associated comorbidities affects the quality of patients' life. We investigated the effects of pentylenetetrazole (PTZ) exposure in zebrafish cognitive performance on inhibitory avoidance test. The animals were exposed to 7.5 mM PTZ for 10 min, in the acquisition (before training) and in the consolidation memory phases (after training). In the acquisition phase, the animals were submitted to PTZ-induced seizures and trained in periods of 1, 24, or 48 h after exposure, and 24 h after training were tested. In the consolidation phase, animals were trained and exposed to PTZ 10 min after training and were tested 24 h later. Control groups in periods of 1, 24, or 48 h before or 10 min after training showed a significantly increased latency to enter the dark compartment. The latencies between training and test sessions did not differ in PTZ groups of animals exposed and trained 1 and 24 h or exposed to PTZ 10 min after training. At 48 h, animals exposed to PTZ showed an increased latency to enter the dark compartment. Animals exposed to PTZ and trained 1 h later increased the traveled distance, when compared to the control group. Traveled distance did not differ in animals that were exposed to PTZ and trained 24 and 48 h, or 10 min after training. Our findings indicate that PTZ causes a cognitive deficit in the pre-and post-training phase, allowing us to explore the influence of seizures at different memory phases.

Automated summary

Epilepsy affects patients' quality of life, and our study on zebrafish shows that PTZ exposure can lead to cognitive deficits.