Shen Yi, Zhuang Pei, Lin Bao-Qin, Zhang Wan-Yu, Cy Chiou George
Institute of Ocular Pharmacology, College of Medicine, Texas A&M Health Science Center, College Station, TX 77843, USA.
Int J Ophthalmol. 2010;3(3):205-10. doi: 10.3980/j.issn.2222-3959.2010.03.06. Epub 2010 Sep 18.
To study the effects of Tetramethylpyrazine (TMP) on retinal pigment epithelium (RPE) degeneration, choroidal blood flow and oxidative stress of RPE cells.
The 35mg/kg NaIO(3)-induced RPE degeneration rat eyes was given 25µg 1% TMP eye drops 3 times a day for 7 days before NaIO(3) injection, and then 2 to 4 weeks after NaIO(3) injection. RPE function was measured with c-wave of electroretinogram (ERG). Colored microsphere technique was used for in vivo experiments to determine the choroidal blood flow in ocular hypertensive (40mmHg) rabbit eyes. Methylthiazoltetrazolium (MTT) assay was used to study in vitro effect of TMP on various oxidants induced injury in the hRPE (ARPE-19 (ATCC, Manassas, VA, USA)).
Two weeks after NaIO(3) injection, the amplitude of ERG c-wave fell markedly in NaIO(3) group to 36% of control group(P<0.01). No apparent difference was observed in TMP+NaIO(3) group. Four weeks later, the NaIO(3) group fell to 46% of control group (P<0.01), while the TMP+NaIO(3) group fell to only 77% of control group (P<0.01). There was a 67% reversal of the ERG c-wave by TMP as compared to NaIO(3) group(P<0.01). The choroidal blood flow was significantly increased at all time points (at 30, 60 and 120 minutes after TMP instillation) as compared with corresponding controls. TMP had no effect on hypoxia-(1% O(2)), t-BHP- and H(2)O(2)-induced damage in RPE cells. 10(g/mL TMP could reverse 1 and 3mM NaN(3)-induced loss of viability of RPE by 18.5% (P<0.01) and 23% (P<0.01), respectively. 30µg/mL TMP could reverse 30 and 100mM NaIO(3) induced loss of viability of RPE by 18.1% (P<0.05) and 16.8% (P<0.01), respectively.
TMP can significantly protect RPE from NaIO(3) induced degeneration in vivo and oxidative stress in vitro and can increase choroidal blood flow markedly in vivo.
研究川芎嗪（TMP）对视网膜色素上皮（RPE）变性、脉络膜血流及RPE细胞氧化应激的影响。
在注射碘酸钠（NaIO₃）前7天，对35mg/kg NaIO₃诱导的RPE变性大鼠眼，每天滴注3次25μg 1% TMP眼药水，共7天，然后在注射NaIO₃后2至4周继续滴注。用电视网膜图（ERG）的c波测量RPE功能。采用彩色微球技术进行体内实验，以测定高眼压（40mmHg）兔眼的脉络膜血流。采用甲基噻唑四氮唑（MTT）法研究TMP对人RPE（ARPE-19（美国弗吉尼亚州马纳萨斯市美国典型培养物保藏中心））中各种氧化剂诱导损伤的体外作用。
注射NaIO₃后2周，NaIO₃组ERG c波振幅显著下降至对照组的36%（P<0.01）。TMP+NaIO₃组未观察到明显差异。4周后，NaIO₃组降至对照组的46%（P<0.01），而TMP+NaIO₃组仅降至对照组的77%（P<0.01）。与NaIO₃组相比，TMP使ERG c波逆转了67%（P<0.01）。与相应对照组相比，在所有时间点（TMP滴注后30、60和120分钟）脉络膜血流均显著增加。TMP对缺氧（1% O₂）、叔丁基过氧化氢（t-BHP）和过氧化氢（H₂O₂）诱导的RPE细胞损伤无影响。10μg/mL TMP可分别使1mM和3mM叠氮化钠（NaN₃）诱导的RPE细胞活力丧失逆转18.5%（P<0.01）和23%（P<0.01）。30μg/mL TMP可分别使30mM和100mM NaIO₃诱导的RPE细胞活力丧失逆转18.1%（P<0.05）和16.8%（P<0.01）。
TMP可在体内显著保护RPE免受NaIO₃诱导的变性，在体外减轻氧化应激，并可在体内显著增加脉络膜血流。
