Effect of N-methyl-D-aspartate-induced infantile spasms on serum corticosterone and adrenocorticotropic hormone levels and hippocampal CRHmRNA expression in young rats / 中华神经医学杂志

ABSTRACT

Objective To study the effect ofN-methyl-D-aspartate (NMDA)-induced seizures on corticosterone and adrenocorticotropic hormone (ACTH) levels and hippocampal CRHmRNA expression in young rats.Methods Wistar rats at P11 were used in our study and randomly divided into NMDA-induced seizure group (n=20) and control group (n=20); P11 rats of NMDA-induced seizure group received intraperitoneal injection of 7 mg/kg NMDA; normal saline was given to the control group;three h after that,the behavioristics changes were observed,and epilepsy rating was performed.And then,these rats were sacrificed; corticosterone and ACTH levels were determined using radio immunoassay;oligonucleotide CRH mRNA probe was labeled with in situ hybridization.Results The levels of corticosterone and ACTH in the control group ([7.95±0.92] ng/mL and [64.17±6.15] pg/mL) were obviously higher than those in the NMDA-induced seizure group ([13.34 ±2.18] ng/mL and [115.9 ± 16.8] pg/mL),with significant differences (t=10.198,P=0.000; t=12.91,P=0.000).In situ hybridization of CRH mRNA showed that the rate of CRH mRNA-positive cells in the hippocampus of control group was 15％ (3/20),which was significantly lower than that in the NMDA-induced seizure group (60％; x2=8.640,P=0.003).Conclusion serum corticosterone,ACTH and hippocampal CRH mRNA levels in NMDA-induced seizure rats are significantly increased,indicating that pituitary-adrenal axis is activatedby NMDA-induced seizures in young rats.