RRC ID 172
Author Matsumoto M, Higuchi K, Togashi H, Koseki H, Yamaguchi T, Kanno M, Yoshioka M.
Title Early postnatal stress alters the 5-HTergic modulation to emotional stress at postadolescent periods of rats.
Journal Hippocampus
Abstract Several lines of evidence have shown that traumatic events during the early postnatal stage might precipitate long-lasting alteration in the functional properties underlying emotional expression. The aim of the present study was to examine whether the early postnatal stress alters the 5-HTergic mechanism underlying regulation of emotional stress, focusing on the 5-HT(1A) receptor-mediated synaptic responses in adult rats. Pups were exposed to aversive stimulus, footshock (FS) at the postnatal period of the second (2W) and the third week (3W). At postadolescent period (10-12-week-old), electrophysiological and behavioral studies were performed. The 5-HT(1A) receptor agonist tandospirone (10 mg/kg body wt, i.p.) blocked the long-term potentiation (LTP) in the hippocampal CA1 field of 3W-FS, as well as non-FS control, whereas this inhibition was not observed in 2W-FS group. Fear-related freezing behavior observed during exposure to contextual fear conditioning markedly attenuated in 2W-FS, but not in 3W-FS. These data suggest that aversive stress exposed at 2W is attributable to changes in the 5-HT(1A) receptor-mediated synaptic plasticity, which may be responsible for the attenuation of freezing behavior. Thus, 5-HT(1A) receptors appear to play a key role in the 5-HTergic mechanism underlying regulation of emotional stress on the postnatal development of the brain. In other words, the second postnatal week may be the "critical period" for establishing proper behavioral responses to emotional stress in adult rats. (c) 2005 Wiley-Liss, Inc.
Volume 15(6)
Pages 775-81
Published 2005
DOI 10.1002/hipo.20100
PMID 15999341
MeSH Aging / metabolism* Animals Animals, Newborn Avoidance Learning / drug effects Avoidance Learning / physiology Disease Models, Animal Electric Stimulation / adverse effects Emotions / drug effects Emotions / physiology* Fear / drug effects Fear / physiology Hippocampus / growth & development* Hippocampus / metabolism Hippocampus / physiopathology Long-Term Potentiation / drug effects Long-Term Potentiation / physiology Male Neural Pathways / growth & development* Neural Pathways / metabolism Neural Pathways / physiopathology Neuronal Plasticity / drug effects Neuronal Plasticity / physiology Rats Rats, Wistar Receptor, Serotonin, 5-HT1A / metabolism Serotonin / metabolism* Serotonin 5-HT1 Receptor Agonists Serotonin Receptor Agonists / pharmacology Stress Disorders, Post-Traumatic / metabolism Stress Disorders, Post-Traumatic / physiopathology Stress, Psychological / metabolism* Stress, Psychological / physiopathology Synaptic Transmission / drug effects Synaptic Transmission / physiology
IF 3.966
Times Cited 29