PT  - JOURNAL ARTICLE
AU  - Amarylis Velez-Perez
AU  - Mary K. Holder
AU  - Sam Fountain
AU  - Jeffrey D. Blaustein
TI  - Estradiol Increases Microglial Response to Lipopolysaccharide in the Ventromedial Hypothalamus during the Peripubertal Sensitive Period in Female Mice
AID  - 10.1523/ENEURO.0505-19.2020
DP  - 2020 Jul 01
TA  - eneuro
PG  - ENEURO.0505-19.2020
VI  - 7
IP  - 4
4099  - http://www.eneuro.org/content/7/4/ENEURO.0505-19.2020.short
4100  - http://www.eneuro.org/content/7/4/ENEURO.0505-19.2020.full
SO  - eNeuro2020 Jul 01; 7
AB  - Sensitive periods are times of development during which the effects of experience are unusually strong and long lasting. The peripubertal period has emerged as one such sensitive period, and a single administration of lipopolysaccharide (LPS) during this time reduces hormone-induced sexual behavior in adult female mice. During periods of high synaptic turnover, maturation, and elimination, as occurs during this sensitive period, microglia are particularly active. Estradiol also regulates microglial numbers, morphology, and activation. In addition, a good deal of evidence suggests that estradiol may confer this vulnerability to the effects of a stressor during the peripubertal period. Therefore, we investigated the effects of estradiol on microglial morphology, cytokine levels, and the sickness response to LPS. Estradiol levels were manipulated by implanting an estradiol-filled SILASTIC capsule (or oil-filled control) in ovariectomized mice or by administering the aromatase inhibitor, formestane (or oil control), to ovary-intact mice. We found that (1) estradiol elevates basal microglial Iba1 immunoreactivity in the ventromedial nucleus of the hypothalamus (VMH), (2) LPS induces higher levels of proinflammatory cytokines in the presence of estradiol, and (3) LPS causes hypothermia in the presence of estradiol. Taken together, these data suggest that estradiol enhances the effect of LPS during the pubertal sensitive period.