Central Phoenixin Protective Role on Pentylenetetrazol-Induced Seizures during Various Stages of the Estrous Cycle among Rats

It is known that phoenixin-۱۴ (PNX-۱۴) has a mediatory role in reproduction; however, there is no report on the role of the PNX-۱۴ on epilepsy. Therefore, this study aimed to investigate the antiepileptic effects of the PNX-۱۴ on the pentylenetetrazol (PTZ)-induced epilepsy in the stages of the estrous cycle among rats. A total of ۱۶۸ adult female Wistar rats were randomly divided into seven groups, including control (intracerebroventricular injection was performed with saline), PNX-۱۴ (۵ µg), PNX-۱۴ (۱۰ µg), bicuculline (competitive antagonist of GABAA receptors; ۵ nmol)+PNX-۱۴ (۵ µg), bicuculline (BIC) (۵ nmol)+PNX-۱۴ (۱۰ µg), saclofen (competitive antagonist of GABAB receptors; ۲.۵ µg)+PNX-۱۴ (۵ µg), and saclofen (۲.۵ µg)+PNX-۱۴ (۱۰ µg) in proestrus, estrus, metestrus, and diestrus. Afterward, the control and treatment groups were followed by intraperitoneal administration of ۸۰ mg/kg PTZ. Initiation time of myoclonic seizures (ITMS), initiation time of tonic-clonic seizures (ITTS), seizure duration (SD), and mortality rate (MR) were monitored and recorded for ۳۰ min. According to the results, PNX-۱۴ alone significantly reduced the SD and seizure mortality in all phases of estrus (P<۰.۰۵). The injection of PNX-۱۴ with BIC significantly reduced SD and seizure mortality in all estrus phases (P<۰.۰۵). PNX-۱۴ alone increased both ITMS and ITTS in all phases of estrus (P<۰.۰۵). Furthermore, the injection of PNX-۱۴ with BIC significantly reduced the effects of the PNX-۱۴ on ITMS and ITTS in all estrus stages (P<۰.۰۵). These results showed that the antiepileptic activity of PNX-۱۴ was probably mediated by GABAA receptors, and this effect was more prominent during the luteal phase than the follicular phase.

کلیدواژه ها:

Estrus cycle ، Pentylentetrazole ، Phoenixin ، rat