临床儿科杂志 ›› 2015, Vol. 33 ›› Issue (4): 368-.doi: 10.3969 j.issn.1000-3606.2015.04.020

• 实验研究 • 上一篇    下一篇

枸橼酸咖啡因对新生大鼠缺氧缺血性脑损伤后神经细胞增生与凋亡及长期学习能力的影响

徐发林,王彩红,张彦华,郭佳佳,程慧清   

  1. 郑州大学第三附属医院新生儿科( 河南郑州 450052)
  • 收稿日期:2015-04-15 出版日期:2015-04-15 发布日期:2015-04-15
  • 通讯作者: 徐发林 E-mail:xufalin72@126.com
  • 基金资助:
    河南省教育厅自然科学研究计划项目(No.13A320664);河南省高等学校青年骨干教师资助计划(No.2012ggjs-015);郑州市2013 年科技创新团队项目(No.131PCXTD621)

Effects of caffeine citrate on neuronal proliferation and apoptosis and long-term learning ability in neonatal rats with hypoxia-ischemic brain damage

XU Falin, WANG Caihong, ZHANG Yanhua, GUO Jiajia, CHENG Huiqing   

  1. Department of Neonatology, The Third Affiliated Hospital of Zhengzhou University, Zhengzhou 450052, Henan, China
  • Received:2015-04-15 Online:2015-04-15 Published:2015-04-15

摘要: 目的 研究枸橼酸咖啡因(CC)对新生大鼠缺氧缺血性脑损伤(HIBD)后神经细胞增生与凋亡及长期学习记忆能力的影响。方法 7日龄SD新生大鼠随机分为假手术组、HIBD组、CC组,每组16只;HIBD组及CC组经左颈总动脉结扎并缺氧制作HIBD模型,CC组在HI前、HI后0 min、24 h、48 h、72 h 给予CC 20 mg/kg腹腔注射,假手术组和HIBD组分别在同一时间点给予等量生理盐水腹腔注射;同时从生后10日龄起腹腔注射5-溴脱氧尿嘧啶核苷(BrdU)标记新生细胞,剂量50 mg/kg,每12 h 1次,共5次。12日龄时每组随机选取8只大鼠处死,免疫组织化学染色检测海马齿状回颗粒下层5-溴脱氧尿嘧啶核苷(BrdU)和海马CA1区活化半胱氨酸天冬氨酸蛋白酶(活化Caspase-3)的表达情况,TUNEL法测定海马CA1区神经细胞凋亡情况,其余各组大鼠28日龄时行Y迷宫学习和记忆能力测试。结果 三组新生大鼠脑组织中均可见BrdU阳性细胞,差异有统计学意义(F=101.38,P<0.01);HIBD组、CC组BrdU阳性细胞数均较假手术组增多,差异有统计学意义(P<0.05)。三组新生大鼠海马CA1区均可见活化 Caspase-3 阳性细胞,差异有统计学意义(F=379.77,P<0.01);CC组活化 Caspase-3 阳性细胞较HIBD组显著减少,但仍多于假手术组,差异有统计学意义(P<0.05)。三组新生大鼠海马CA1区中均可见TUNEL阳性细胞,差异有统计学意义(F=505.92,P<0.01),以HIBD组最多,假手术组最少,两两比较差异均有统计学意义(P<0.05)。Y迷宫实验结果,各组大鼠达标所需训练总次数的差异有统计学意义(F=32.05,P<0.01),以HIBD组所需训练次数最多。24 h后正确反应率在三组间的差异也有统计学意义(F=24.99,P<0.01),以HIBD组大鼠正确反应率最低。结论 枸橼酸咖啡因可以改善HIBD大鼠长期学习记忆力,其机制可能与通过减少缺氧缺血后神经细胞的凋亡有关。

Abstract: Objective To investigate the effects of caffeine citrate (CC) on the neuronal proliferation and apoptosis and longterm learning ability in neonatal rats with hypoxia-ischemic brain damage (HIBD). Methods Forty-eight 7-day-old Sprague-Dawley neonatal rats were randomly divided into 3 groups: sham operation group (n=16), HIBD group (n=16), HIBD + caffeine citrate group (CC group, n=16). Rats in HIBD and CC groups received ligation of left common carotid artery followed by 2 hours of hypoxia to establish HIBD model. Rats in CC group were injected intraperitoneally with CC (20 mg/kg) before and at 0 min, 24 h, 48 h, and 72 h after hypoxia-ischemic (HI), and rats in the other two groups were injected intraperitoneally with an equal volume of normal saline at the corresponding time. Meanwhile, from postnatal day 10, each rat was injected intraperitoneally with 5-bromo-2’-deoxyuridine (BrdU) (50 mg/kg) for 5 consecutive times, once every 12 h. On postnatal day 12, BrdU in the hippocampal dentate gyrus and cleaved caspase-3 in the hippocampal CA1 area were detected by immunohistochemistry, and neuronal apoptosis in hippocampal CA1 area were detected by TUNEL staining. On postnatal day 28, long-term learning and memory ability of rats was tested by Y maze. Results There was significant difference in the number of BrdU-positive cells in brain tissues of rats among three groups (F=101.38, P<0.01). The BrdU-positive cells in HIBD group and CC group were significantly more than those in sham operation group (P<0.05). There was significant difference in the number of cleaved caspase-3-positive cells in hippocampal CA1 area among three groups (F=379.77, P<0.01). The cleaved caspase-3-positive cells in CC group were significantly fewer than those in HIBD group but significantly more than those in sham operation group (P<0.05). The TUNEL-positive cells in hippocampal CA1 area were significantly different among three groups (F=505.92, P<0.01) which was most in HIBD group and fewest in sham operation group and significant difference was found through multiple comparison (P<0.05). The total learning number of avoiding electric shock tested by Y maze was significantly different among three groups (F=32.05, P<0.01) which was most in HIBD group. Correct response rate was significantly different among three groups (F=24.99, P<0.01) which was lowest in HIBD group. Conclusions Caffeine citrate can improve the ability of long-term learning and memory in neonatal rats with hypoxia-ischemic brain damage, the mechanism of which may be related to reducing the neuronal  apoptosis after hypoxia ischemia.