Effects of Levetiracetam on neural tube development and closure of the chick embryos in ovo.

Purpose: Effects of Levetiracetam (LEV) within its therapeutic range at a 50 mg/kg dose for the chick embryo in ovo has been studied in order to demonstrate whether LEV would effect neural tube closure at the macroscopic morphology or LEV administered embryos still encounter neuroglial detrimental effects at the histological level.

Methods: Embryos were randomly seperated into control (n = 20) and study (n = 20) groups. The eggshell was windowed at specifically 24 h of incubation, and area underlying the membrane was excised to allow injection with 4.5 μl LEV in the study group, while physiologic saline (0.045 ml) were injected in the control group and each egg were re-incubated for 48 h more. Then, histological and immunohistochemical evaluation of the subjects were done.

Results: Macroscopic evaluation revealed immaturity of the placental vessel network in number and width for the study group in comparison to the controls. Defects of migration, decrease in the crista neuralis content, delay of the basal plates structures in the formation of the usual configuration, and delay in the cellular proliferation and the delay of development for the central nervous system were determined in the LEV-exposed group. Immunostaining of S100 proteins in this study has clearly demonstrated increased expression patterns of both neuroglial and neuronal cell populations. Toluidine blue stainings revealed mostly bipolar, differentiating neurons and crista neuralis cells which is concordant with active migration and differentiation.

Conclusions: LEV found that delay in the closure of the neural tube and microcephalic fetuses disturb further morphological, biochemical, and functional development.