Effect of acute and chronic intrahippocampal microinjection of ghrelin on pentylenetetrazole-induced seizures in rats

Abstract

Objectives: Epilepsy is one of the most common neurological conditions. Though there are many therapeutic strategies for epilepsy but most of these treatment modalities have been relatively successful in suppressing seizures. Ghrelin, a gastric peptide with key action on food intake, has been recently recognized as a potential anticonvulsant agent. In the present study, we investigated the effect of acute and chronic injection of ghrelin on pentylenetetrazole (PTZ)-induced seizure in rats. Methods: Forty male Wistar rats were bilaterally microinjected with saline or one of the different doses of ghrelin (0.3, 1.5, and 3.0 nmol/?l/side). Ghrelin was administered into dorsal hippocampus thirty minutes before intraperitoneal injection of PTZ. The effect of chronic administration of ghrelin into dorsal hippocampus was investigated in twenty male wistar rats. The rats were bilaterally microinjected with saline (1 ?l/side) or ghrelin with effective dose (0.3 nmol/?l/side) for ten- day. In tenth day, thirty minutes after saline or ghrelin microinjection, PTZ was injected intraperitoneally. Results: Ghrelin, at a dose of 0.3 nmol/?l, significantly (p<0.001) decreased the duration and seizure severity. Chronic microinjection of ghrelin significantly (p<0.001) attenuated the duration and severity of the seizure induced by PTZ. Conclusion: The present study provides evidences that the intrahippocampal microinjection of ghrelin has an inhibitory effect against PTZ-induced seizure.