Effects of treatment with clinically relevant valproate, carbamazepine, oxcarbazepine, topiramate, lamotrigine and levetiracetam on ovarian folliculogenesis in young rats.

AIM: To determine the effects of valproate (VPA), carbamazepine (CBZ), oxcarbazepine (OXC), topiramate (TPM), lamotrigine (LTG), and levetiracetam (LEV) on ovarian folliculogenesis in young rats.

METHODS

Forty-nine female Wistar rats, aged 21-24 days, were divided equally into 7 experimental groups. These were given tap water over 21-24 days (control group), 300 mg/kg of VPA, 150 mg/kg of CBZ, 150 mg/kg of OXC, 100 mg/kg of TPM, 10 mg/kg of LTG, or 50 mg/kg of LEV daily in 2 doses via oral gavage until the end of puberty. At the end of the study, the estrous cycle of each rat was monitored daily, and those rats in pro-estrus or di-estrus were sacrificed and the ovaries removed. Serial sections obtained from the ovaries were stained with hematoxylin and eosin, and the corpora lutea and follicles were enumerated. Apoptotic cells were detected using the TUNEL technique. Various serial sections were immunohistochemically stained with proliferating cell nuclear antigen (PCNA), growth differentiation factor (GDF)-9, caspase-3, caspase-9, transforming growth factor beta 1 (TGF-1), and epidermal growth factor (EGF), and evaluated and photographed under a light microscope.

KEY FINDINGS: The number of corpora lutea was significantly increased in the VPA, CBZ, OXC, and LTG groups compared to the control group (p < 0.001). The number of TUNEL-positive ovarian follicles was 3.3 ± 1.1 (median, 3), 6.1 ± 0.9 (median, 6), and 5.7 ± 0.8 (median,6) in the control, OXC and LEV groups, respectively (p < 0.001). The number of TUNEL-positive granulosa cells was higher in all the groups treated with antiepileptics, with the exception of the TPM group, compared to the control group (p < 0.001). HSCOREs for immunohistochemical staining using PCNA, GDF-9, TGF-1 and EGF were significantly higher in the control group than in the others (p < 0.001). HSCORE for staining using caspase-3 was significantly higher in the VPA, CBZ, OXC and LEV groups, while the HSCORE was significantly lower in the TPM group than in the control group. HSCORE for staining using caspase-9 was significantly higher in the VPA, CBZ and OXC groups, while it was significantly lower in the TPM group than in the control group (p < 0.001).

SIGNIFICANCE: Exposure to VPA, CBZ, OXC, TPM, LTG and LEV caused different levels of impaired folliculogenesis in young rats.