Abstract：OBJECTIVE: To study the effect of maternal isolation stress on the epilepsy susceptibility in young rats and the possible mechanism. METHODS: Sixty Sprague-Dawley young rats were randomly divided into a normal control and two maternal isolation groups that were subjected to maternal isolation for 15 min or 3 hrs daily on postnatal days 2-17. On postnatal day 18, an amygdala kindling test was performed to induce seizures. The expression of GABAA receptor α1 in the hippocampus was determined by immunohistochemisty. RESULTS: The weights were reduced, the threshold of amygdala kindling and the stimulation number for full kindling decreased significantly, and seizures were more severe in the maternal isolation 3 hrs group compared with the normal control group. The expression of GABAA receptor α1 in the hippocampus CA1 area in the maternal isolation 3 hrs group decreased significantly compared with that in the normal groups. There were no significant differences in the aspects above mentioned between the maternal isolation 15 min and normal control groups. CONCLUSIONS: The stress of early daily maternal isolation for 3 hrs may affect adversely brain development and increase epilepsy susceptibility in young rats. The decreased expression of GABAA receptor α1 in the hippocampus may contribute to the potential mechanism.［Chin J Contemp Pediatr, 2010, 12 (8):662-665］
［1］Galanopoulou AS. GABAA receptors in normal development and seizures: friends or foes? ［J］. Curr Neuropharmacol, 2008, 6(1):1-20.
［2］Dulac O, Nabbout R, Plouin P, Chiron C, Scheffer I. Early seizures: causal events or predisposition to adult epilepsy? ［J］. Lancet Neurol, 2007, 6(7):643-651.
［3］Montpied P, Weizman A, Weizman R, Kook KA, Morrow AL, Paul SM. Repeated swim-stress reduces GABAA receptor alpha subunit mRNAs in the mouse hippocampus ［J］. Brain Res Mol Brain Res, 1993,18(3):267-272.
［4］Lai MC, Holmes GL, Lee KH, Yang SN, Wang CA, Wu CL, et al. Effect of neonatal isolation on outcome following neonatal seizures in rats—the role of corticosterone ［J］. Epilepsy Res, 2006，68(2):123-136.
［6］Jones C, Gaurav K, O′Briena J, Morrisd M, Sundra M, Michel R. Anxiolytic effects of rapid amygdala kindling, and the influence of early life experience in rats ［J］. Behavioural Brain Research, 2009, 203(1):81-87.
［7］Edwards HE, Dortok D, Tam J, Won D, Burnham WM. Prenatal stress alters seizure thresholds and the development of kindled seizures in infant and adult rats ［J］. Horm Behavior, 2002, 42(4):437-447.
［8］Ogris W, Lehner R, Fuchs K, Furtmuller B, Hoger H,Gregg E, et al. Investigation of the abundance and subunit of GABA receptor subtypes in the cerebellum α1-subunit-deficient mice ［J］. J Neurochem, 2006, 96(1):136-147.
［10］Loup F, Wieser HG, Yonekawa Y, Aguzzi A, Fritschy JM. Selective alterations in GABAA receptor subtypes in human temporal lobe epilepsy ［J］. J Neurosci, 2000, 20(14):5401-5419.
