Childs Nerv Syst (2004) 20:176–182 DOI 10.1007/s00381-003-0901-3 ORIGINAL PAPER Yig ˘it Uyanıkgil Meral Baka Mine Yurtseven Mehmet Turgut The effect of experimental epilepsy induced by penicillin administration during pregnancy on nestin expression in the immature rat cerebellum A light, electron microscopic, and immunohistochemical study Received: 1 December 2003 Published online: 10 February 2004  Springer-Verlag 2004 Y. Uyanıkgil · M. Baka · M. Yurtseven Department of Histology and Embryology, Ege University School of Medicine, Izmir, Turkey M. Turgut Department of Neurosurgery, Adnan Menderes University School of Medicine, Aydın, Turkey M. Turgut ( ) ) Cumhuriyet Mahallesi, Cumhuriyet Caddesi, No: 6 Daire: 7, 09020 Aydın, Turkey e-mail: drmturgut@yahoo.com Tel.: +90-256-2134874 Fax: +90-256-2120146 Abstract Introduction: Recent knowledge regarding the effect of epileptic seizures in pregnant women on newborns was limited and, there- fore, it was difficult to suggest the proper clinical guidelines and to take precautions against it. Studies evalu- ating the morphological effects of epileptic seizure during pregnancy on newborns in various experimental models are valuable. Therefore, the current study was designed to inves- tigate the morphological changes in the cerebellum of newborn pups of rats subjected to experimental epi- lepsy during pregnancy. Materials and methods: Swiss Albino rats were divided into three groups (six animals in each). In the first group (experi- mental group) an acute grand mal epileptic seizure was induced by 400 IU penicillin-G administration into their intrahippocampal CA3 re- gion with a stereotaxic device during the 13th day of their pregnancy. The second group (intrahippocampal sa- line-injected sham group) and the third group (untreated animals) were the control groups. On the 1st neo- natal day, pups were perfused with intracardiac fixative solution under anesthesia, and newborn cerebellums were dissected surgically for light and electron microscopic studies. Results: In an immunohistochemical study using Rat-401 monoclonal an- tibody and peroxidase, the interme- diate filament nestin was detected in the developing cerebellar tissue. Histologically, normal migration and cerebellar maturation were deter- mined in the newborn rat cerebellum in the control and sham-operated groups. It was observed that the morphological structure of the cere- bellar cortex in the experimental group was compromised in the early embryonal period. In contrast to the control and sham groups, it was found that nestin (+) cell density was increased in the experimental epilep- sy group. Conclusions: It has been concluded that epileptic convulsions during embryonic life may cause early neurogenesis and delayed mat- uration, which explains the harmful effects of epileptic grand mal sei- zures, hypoxia, and obstetric trauma to the embryo at the early stage of neuronal differentiation. However, further studies are necessary to in- vestigate epileptic pregnant phenom- ena and to characterize the possible relationship between epilepsy and congenital malformations as well as mental retardation. Keywords Cerebellum · Epilepsy · Pregnancy · Rat · Nestin