Role of estradiol in mediation of etomidate-caused seizure-like activity in neonatal rats.
BACKGROUND
The goal of this study was to investigate the effect of estradiol in mediation of electroencephalogram (EEG) abnormality induced by etomidate in neonatal rats.


METHODS
Sprague-Dawley rats were anesthetized using intraperitoneal etomidate for 2 h on postnatal days (P) 4, 5, or 6 and recorded electroencephalogram in two ways. First, pups were recorded EEG two and a half hours under etomidate anesthesia, in subgroups, estradiol receptor antagonist ICI182780 and estradiol synthase inhibitor formestane were given subcutaneously in male rats 15 min prior to etomidate. Second, pups were anesthetized with etomidate for 2 h on P4,5 or 6 and then recovered from anesthesia, EEG were recorded for one hour in two postnatal periods of P9-P11 and P14-P16. Subgroup rats that received bumetanide, NKCC1 inhibitor, to test the NKCC1-GABAAR signaling effect on neonatal brain development, negative control groups and maternally separated for 2 h on P4, 5, or 6 were studied in 16 groups. Each group's n was = 8.


RESULTS
Male pups showed more severe seizure-like activities than female pups in P4-P6 under etomidate anesthesia. Pups pretreated with ICI182780 and formestane showed a less abnormalities of EEG in male rats. Etomidate caused seizure-like activity in P4-P6 could extend to P9-P11, but not seen in P14-P16, Pretreated with bumetanide only alleviated abnormalities in male pups other than female in P9-P11.


CONCLUSIONS
Estradiol involves in the NKCC1-GABAAR mediated seizure-like activity caused by etomidte in neonatal rats and these the abnormality lasts near two weeks.
['Yang|Chunyao|C|', 'Li|Changsheng|C|', 'Sun|Jing|J|', 'Lu|Xihua|X|']
D018686:Anesthetics, Intravenous D000818:Animals D001921:Brain D002034:Bumetanide D004569:Electroencephalography D004958:Estradiol D065171:Estrogen Receptor Antagonists D005045:Etomidate D005260:Female D000077267:Fulvestrant D008297:Male D051381:Rats D017207:Rats, Sprague-Dawley D011960:Receptors, Estrogen D012640:Seizures D012737:Sex Factors D049994:Sodium Potassium Chloride Symporter Inhibitors
Estradiol Neonate EEG Etomidate Neurodevelopment Seizures