Role of the NMDA receptor in cognitive deficits, anxiety and depressive-like behavior in juvenile and adult mice after neonatal dexamethasone exposure.
Postnatal dexamethasone (DEX) therapy has been used to treat or prevent chronic lung disease after premature births. However, there are many reports of long-term negative neurodevelopmental sequelae following this treatment. In contrast, hydrocortisone (HYD), which has fewer neurodevelopment adverse effects, is used as an alternative for DEX. In this study, we report that neonatal DEX exposure (days 1-3) caused alterations of amino acids affecting N-methyl-d-aspartate (NMDA) receptor neurotransmission in mouse brains. Neonatal DEX, but not HYD, exposure (days 1-3) significantly decreased the GluN2B subunit of NMDA receptor in the hippocampus at juvenile and adult stages. Mice treated with DEX showed cognitive deficits, as well as anxiety and depressive-like behavior at juvenile and adult stages. In contrast, mice treated with HYD (days 1-3) showed no behavioral abnormalities at these stages. In the DEX suppression test, plasma levels of corticosterone in mice exposed neonatally to DEX and HYD were significantly higher at juvenile, but not adult stages. Pretreatment with Ro 63-1908, an antagonist at GluN2B subunit, 30min before each injection of DEX, prevented cognitive deficits, as well as anxiety and depressive-like behavior in juvenile and adult mice. Interestingly, subsequent repeated (days 29-33) administration of Ro 63-1908 or L701324, an antagonist of the glycine modulatory site on the NMDA receptor, significantly suppressed behavioral abnormalities in juvenile and adult mice after neonatal DEX exposure. These results indicate that neonatal DEX, but not HYD, exposure produced behavioral abnormalities in juvenile and adult mice by altering glutamatergic neurotransmission via the NMDA receptor. The NMDA receptor antagonists may prevent or treat these DEX-induced neonatal behavioral abnormalities in later life.
Division of Clinical Neuroscience, Chiba University Center for Forensic Mental Health, Chiba, Japan; National Institute on Drug Dependence, Peking University, Beijing, China.
Su-Xia
SX
Li
Division of Clinical Neuroscience, Chiba University Center for Forensic Mental Health, Chiba, Japan.
Yuko
Y
Fujita
Division of Clinical Neuroscience, Chiba University Center for Forensic Mental Health, Chiba, Japan.
Ji-Chun
JC
Zhang
Division of Clinical Neuroscience, Chiba University Center for Forensic Mental Health, Chiba, Japan.
Qian
Q
Ren
Division of Clinical Neuroscience, Chiba University Center for Forensic Mental Health, Chiba, Japan.
Tamaki
T
Ishima
Division of Clinical Neuroscience, Chiba University Center for Forensic Mental Health, Chiba, Japan.
Jin
J
Wu
Division of Clinical Neuroscience, Chiba University Center for Forensic Mental Health, Chiba, Japan. Electronic address: hashimoto@faculty.chiba-u.jp.
Kenji
K
Hashimoto
D000367:Age Factors; D000818:Animals; D000831:Animals, Newborn; D001007:Anxiety / Q000139:chemically induced* / Q000378:metabolism; D001923:Brain Chemistry; D003072:Cognition Disorders / Q000139:chemically induced* / Q000378:metabolism; D003863:Depression / Q000139:chemically induced* / Q000378:metabolism; D003907:Dexamethasone / Q000633:toxicity*; D005260:Female; D005625:Frontal Lobe; D006624:Hippocampus / Q000378:metabolism; D006854:Hydrocortisone / Q000494:pharmacology; D008297:Male; D051379:Mice; D008813:Mice, Inbred ICR; D009043:Motor Activity / Q000187:drug effects; D016194:Receptors, N-Methyl-D-Aspartate / Q000378:metabolism*
C121001:NR2B NMDA receptor; D016194:Receptors, N-Methyl-D-Aspartate; D003907:Dexamethasone; D006854:Hydrocortisone
Adult; Anxiety; Cognition; Depression; Dexamethasone; GluN2B subunit; Hydrocortisone; Juvenile; NMDA receptor; Neonatal