摘要
目的 研究一种新的红细胞源性降压因子 (EDDF)对正常大鼠及左旋硝基精氨酸 (L NNA)高血压大鼠主动脉一氧化氮 (NO) /cGMP通路的影响。方法 30只雄性Wistar大鼠 ,分为对照组及高血压模型组 ,每组 15只。模型制备是通过腹腔注射L NNA(15mg/kg) ,每日 2次 ,连续 4周。应用放免法及3 H 左旋硝基精氨酸 (L arg)掺入等方法分别测定主动脉和血浆cGMP水平及主动脉L arg掺入率。应用免疫组化法对主动脉一氧化氮合酶 (NOS)染色。结果 L NNA组用药后次日血压即开始升高 (18 8kPavs16 4kPa ,P <0 0 5 ) ,以后持续升高并稳定于高水平 ;L NNA组L arg的转化率 (pmol·mg-1蛋白·min-1)明显低于正常组 (13 1± 0 9vs 16 8± 1 2 ,P <0 0 5 )。在L NNA组主动脉cGMP水平 (pmol/g)也明显低于正常组 (14 8± 16vs 186± 12 ,P <0 0 5 )。L NNA组主动脉NOS酶免疫组化染色比对照组明显变浅。EDDF(10 4mg/ml)可使正常大鼠主动脉L arg转化率及cGMP水平明显升高。孵育前后L arg转化率及cGMP水平分别为 16 8± 1 2vs 2 0 1± 0 9(P <0 0 5 )和 187pmol/g± 10pmol/gvs 2 33pmol/g± 14pmol/g(P <0 0 5 )。但EDDF对L NNA大鼠主动脉NOS底物转化率与cGMP水平无显著影响。
Objective To evaluate the effect of EDDF a new erythrocyte derived depressing factor, on the NO/cGMP pathway in aorta of normal rats and rat, with hypertension induced by L NNA. Methods Thirty male Wistar rats aged 10 weeks were divided into two groups: L NNA group and control group, 15 rats for each group. L N G nitro arginine (L NNA) was injected into the abdominal cavity of the rats in the L NNA group at dose of 15 mg/kg twice a day for four weeks. Normal saline was injected the same way in the control group. The levels of cGMP in aorta and plasma were measured by radioimmunoassay and 3?H L arg incorporation. NOS was measured by immunohistochemistry. Results One day after injection of L arg, the blood pressure of the experimental rats began to rise remarkably (18 8 kPa vs 16 4 kPa, P <0 05), and then remained at a high level The L arg transfer rate (pmol·mg -1 ·pr·min -1 ) of aorta in L NNA group was significantly lower than that of control group (13 0±0 9 vs 16 8±1 2 P < 0 05) After incubation with EDDF (10 -4 g/ml), the L arg transfer rate and cGMP level of aorta were remarkably increased in normal rats (20 1±0 9 vs 16 8±1 2, P <0 05 and 233±14 vs 187± 10, P <0 05) The L arg transfer rate and cGMP level of aorta remained unchanged afeter incubation with EDDF in the L NNA group (13 0±0 9 vs 13 2 ±0 3 and 148±16 vs 186±12) The cGMP level (pmol/g) of aorta in L NNA group were obviously lower than that of control rats (148±16 vs 186±12, P <0 05) Immunohistological staining of NOS in aorta was obviously lighter in L NNA group than in control group The immunohistochemical staining intensity in aorta remained the same after incubation with EDDF in L NNA group Conclusion The NO/cGMP pathway might be in charge of vasodilation mechanism of EDDF
出处
《中华医学杂志》
CAS
CSCD
北大核心
2002年第3期194-197,共4页
National Medical Journal of China
基金
国家自然科学基金 (3 0 0 70 2 81)
高等学校博士学科点专项科研基金 (2 0 0 1 2 0 0 3 )
