摘要
目的探讨β受体阻滞剂对一氧化氮(NO)和内皮素(ET)、血压昼夜节律的影响。方法健康雄性SD大鼠128只,体质量250～300g,随机分为4组,分别为早对照组(control morning,CM)、晚对照组(control night,CN)、早灌药组(take medicine morning,TM)和晚药组(take medicine night,TN),每组大鼠32只。TM和TN组每日早、晚7:00给予比索洛尔3mg/kg灌胃,CM和CN组给予相同剂量的安慰剂灌胃。4周后,分别于同日内不同时间点(2:00,8:00,14:00,20:00)用鼠尾血压仪测各组大鼠血压并处死,留取血浆、血清和心肌组织。分别采用放免法和硝酸还原法检测血和心肌组织中ET-1、NO的含量。结果血清和心肌组织中NO和ET-1水平在不同时点之间差异均有统计学意义(P<0.01),各组间差异也有统计学意义(P<0.01)。①血清和心肌组织中NO含量:在2:00时,CM组与CN组比较差异无统计学意义(P>0.05),但TN组比TM组明显降低(P<0.01);在8:00时,CN组高于CM组(P<0.01),TN组也高于TM组(P<0.01);在14:00时CM组和CN组之间差异无统计学意义,而TN组均低于TM组(P<0.05或P<0.01);20:00时CN组血清NO低于CM组(P<0.01),而TN组血清和心肌组织中NO均高于TM组(P<0.05或P<0.01)。②血清和心肌组织中的ET-1水平:在2:00时点,CM组高于CN组(P<0.01),TN组高于TM组(P<0.01);在8:00时,CM组和CN组之间血清ET-1水平差异无统计学意义(P>0.05),而CN组心肌组织ET-1水平高于CM组(P<0.01),TN组血清ET-1水平高于TM组(P<0.01),TN组心肌组织ET-1低于TM组(P<0.01);14:00CM组和CN组之间血清ET-1水平差异无统计学意义(P>0.05),而TN组血清和心肌组织ET-1水平高于TM组(P<0.01);20:00CN组血清和心肌组织ET-1低于CM组(均P<0.01),TN组血清ET-1水平高于TM组(P<0.01),TM组和TN组之间心肌组织ET-1水平差异无统计学意义(P>0.05)。各组血清及组织NO、ET-1均存在典型昼夜节律,振幅有明显差异。结论正常血压大鼠血清和心肌组织ET-1、NO存在典型的昼夜节律特征。比索洛尔可降低ET-1水平,提高血清及心肌组织NO的含量,并影响血压的昼夜节律。
Objective To investigate the effect of β-adrenoceptor blockers on circadian rhythm of nitric oxide（NO） and endothelin（ET）,blood pressure. Methods 128 male SD rats weighted 250-300 g were randomly divided into four groups,control morning（TM）,control night（CN）,take medicine morning（TM）,take medicine night（TN）,each group 32 rats.TM and TN group were given bisoprolol at 7：00 AM and 7：00 PM respectively with intragastric administration 3 mg/kg and CM and CN group were given the same dosage of placebo at 7：00 AM and 7：00 PM respectively.After 4 weeks feeding,we measured all the rats’ blood pressure with rat-tail manometry at different times in one day（2：00,8：00,14：00,20：00）,euthanatized one rat in each group（CM,CN,TM,TN） and collected the plasma,blood serum and myocardial tissues.Radioimmunity method,and acid reductase method were adopted to measure the concentrations and content of ET-1,NO in blood and myocardial tissues. Results The blood serum or cardiac muscle content of NO,ET-1 had statistic significance in different measure times（P〈0.01） and among four groups（P〈0.01）.①At 2：00,the blood serum or cardiac muscle content of NO,ET-1 had no statistic significance between CM and CN group（P〈0.01）,but TN group had significant decreases compared with TM group（P〈0.01）;At 8：00,CM group had significant increases compared with CM group（P〈0.01）,TN group were also higher than TM group（P〈0.01）;At 14：00,CM group showed no statistic significances with CN group,while TN group were lower than TM group（P〈0.05 or 0.01）;At 20：00,the serum content of NO was lower than that of CM group（P〈0.01）,but serum content and cardiac muscle content of NO were both higher that those of TM group（P〈0.05 or P〈0.01）.②At 2：00,the blood serum or cardiac muscle content of ET-1 in CM group were significantlt higher than those of CN group（P〈0.01）,but TN group were significantly higher than those of TM group（P〈0.01）;At 8：00,the blood serum content of ET-1 between CM and CN group showed no significant difference（P〉0.05）,while the cardiac muscle content of ET-1 in CN group was also higher than that of CM group（P〈0.01）;the blood serum content of ET-1 in TN group was higher than that of TM group,the cardiac muscle contentt of ET-1 in TN group was lower than that of TM group（P〈0.01）.At 14：00,in blood serum content of ET-1,CM group showed no statistic significances with CN group,while the blood serum and cardiac muscle content of ET-1 in TN group were higher than those of TM group（P0.01）;At 20：00,the blood serum and cardiac muscle content of ET-1 in CN group were lower than those of CM group（both P〈0.01）,but the serum content ET-1 in TN group was higher that that of TM group（P〈0.01）.The cardiac muscle content of ET-1 between TM group and TN group showed no significant difference（P〉0.05）.The blood serum or cardiac muscle content of NO,ET-1 in different groups possessed the characteristic of circadian rhythm and their amplitudes were different mutually. Conclusion The blood serum and cardiac muscle contents of NO,ET-1 in rats with normal blood pressure had the circadian rhythm,bisoprolol reduces ET contents,raises the blood serum and cardiac muscle contents of NO and influences the circadian rhythm.
出处
《临床荟萃》
CAS
2012年第2期127-131,共5页
Clinical Focus
基金
河北省自然科学基金资助项目(C2007000951)
