安定对大鼠脊髓损伤后细胞凋亡的影响

Effect of diazepam on cell apoptosis in rats with spinal cord injury

目的:探讨安定对大鼠挤压伤模型脊髓损伤后的作用,以及γ-氨基丁酸A型受体拮抗剂荷包牡丹碱和苯二氮受体拮抗剂氟马西尼对此作用的影响。方法:实验于2003-04/2004-11在解放军第四军医大学神经科学研究所完成。选择SD雄性大鼠36只,体质量180～200g,随机分为6组,每组6只。大鼠脊髓挤压伤模型建立后立即给药,对照组给予生理盐水2mL/kg腹腔注射;安定组给予安定10mg/kg腹腔注射;安定+荷包牡丹碱组同时给予安定10mg/kg及荷包牡丹碱2.1mg/kg;安定+氟马西尼组同时给予安定10mg/kg及氟马西尼5mg/kg;荷包牡丹碱组仅给予荷包牡丹碱腹腔注射2.1mg/kg;氟马西尼组给予氟马西尼5mg/kg。药物作用72h后采用脊髓原位末端标记法观察各组大鼠凋亡细胞分布情况,并比较每张切片平均凋亡细胞数。结果:36只大鼠全部进入结果分析。平均每张切片凋亡细胞数:安定组明显小于对照组犤(69.15±14.25)个,(130.08±30.40)个,卓艹(t=4.4457,P<0.01)犦;安定+荷包牡丹碱组及安定+氟马西尼组犤(89.75±14.45)个,(97.76±14.85)个犦均明显大于安定组(t=2.4868,3.4051,P<0.01),但小于对照组(t=2.93522.3399,P<0.01),而此两组结果比较差异无显著性意义(P>0.05)。荷包牡丹碱组及氟马西尼组犤(137.38±29.11)个,(131.53±28.68)

AIM: To study the effect of diazepam on crush injury models of rats with spinal cord injury,and the effect of bicuculline,a gamma aminobutyric acid type A receptor antagonist, and flumazenil, a benzodiazepines receptor antagonist.METHODS: The experiment was finished in the Institute of Neurosciences, Fourth Military Medical University of Chinese PLA from April 2003 to November 2004.The 36 SD rats weighing 80- 200 g were divided randomly into 6 groups (n=6): control group was injected with 2 mL/kg saline into abdominal cavity; diazepam group was injected with 10 mg/kg diazepam; diazepam plus bicuculline group was injected with 10 mg/kg diazepam and 2.1 mg/kg bicuculline; diazepam plus flumazenil group was injected with 10 mg/kg diazepam and 5 mg/kg flumazenil; bicuculline group was injected with 2.1 mg/kg bicuculline; flumazenil group was injected with 5 mg/kg flumazenil. The mean positive cell number per section 72 hours after drug administration were observed by using TdT mediated dUTP biotin nick end labeling.RESULTS: All rats were involved in the result analysis.The number of the mean positive cells per section in the diazepam group was less as compared with that in control group (69.15± 14.25 vs 130.08± 30.40, t=4.445 7,P< 0.01); in diazepam plus bicuculline group and diazepam plus flumazenil group, it was more as compared with that in diazepam group(89.75± 14.45, 97.76± 14.85,t=2.486 8,3.4051,P< 0.01), but less than that in control group(t=2.935 2, 2.339 9,P< 0.01), and there was no significant difference between the two groups(P >0.05); also, there was no significant difference among bicuculline group (137.38± 29.11), flumazenil group(131.53± 28.68)and control group(P >0.05).CONCLUSION: Diazepam can effectively decrease the neuronal and glial cell apoptosis in rats with spinal cord injury, and the protective effect of diazepam can be blocked by gamma aminobutyric acid type A receptor antagonist bicuculline and benzodiazepines receptor antagonist flumazenil.