RESUMO
OBJECTIVE@#To determine the changes of mossy fiber sprouting in hippocampus of pre-kindling and post-kindling rats of chronic epilepsy induced by pentylenetetrazole (PTZ).@*METHODS@#Sixty rats were randomly divided into a control group and a PTZ group (PTZ 30 mg/kg, intraperitoneal injection, once daily). The changes of mossy fiber sprouting in hippocampus of pre-kindling and post-kindling rats were examined by Timm staining.@*RESULTS@#Before the occurrence of convulsion confirmed by behavior and EEG, the mossy fiber sprouting was found in the PTZ group. The grade of the mossy fiber sprouting increased with the gradual establishment of kindling effect.@*CONCLUSION@#Mossy fiber sprouting may play an important role in the onset and development of epilepsy.