乌榄叶水提物对应激性高血压大鼠降压作用的研究

目的探讨乌榄叶水提物对应激性高血压大鼠血压和心率的影响.方法用电击足底与噪声结合刺激大鼠4周,建立应激性高血压模型.采取用颈总动脉插管法,通过MedLab生物信号采集处理系统,检测大鼠平均收缩压、舒张压和心率.结果乌榄叶水提物对应激性高血压大鼠有显著的降压作用,其中以舒张压下降最为明显,降压幅度较正常大鼠显著(P＜0.01),作用维持时间更长,同时具有减慢心率作用.结论乌榄叶含有丰富而强效的降压活性成分;降压效果与大鼠基础血压相关.     

乌榄树皮提取物对大鼠血压、心率的影响

目的探讨乌榄树皮水提物对大鼠血压和心率的药效学作用。方法本实验采用颈总动脉插管,MedLab生物信号采集处理系统,测定大鼠血压和心率。实验大鼠随机分为乌榄树皮水提物低剂量组、高剂量组、生理盐水组和阳性药物异搏定对照组。结果该水提物对大鼠血压有快速的降压作用,尤以舒张压为明显,降压效果和作用时间随着药物剂量的增加而加大、延长,且有减慢心率的作用。结论乌榄树皮水提物对正常大鼠有降压和减慢心率的药效作用,并有一定的药物量效关系。     

浅谈乌榄药用的研究进展

目的通过广泛搜集资料，综述乌榄的民间用药和药理作用。结论乌榄除了可以食用外，其根、叶、果均有不同民问药用价值。其果仁可以止血化痰，利水消肿。乌榄叶具有清热解毒，消肿止痛之效。乌榄根主治舒筋活络，祛风去湿。近年来对乌榄叶、果和树皮不同药物部位提取物的动物实验表明：乌榄叶、果和树皮水提物均有快速显著的降压作用，乌榄叶水提物对离体蛙心还有快速显著的负性变力作用。乌榄果还具有抗氧化、抗衰老作用。乌榄在广东资源丰富，但其药用功效并没有得到广泛应用，具有重要的开发作用与意义。     

乌榄叶水提取物对大鼠离体心脏灌流的作用探究

目的探究乌榄叶水提取物对大鼠离体心脏的冠脉流量、心肌收缩力及心率的影响。方法采用Langendorff离体心脏灌流法,通过MedLab生物信号采集处理系统,观察药物对正常大鼠离体心脏的冠脉流量、心肌收缩力及心率的作用。结果乌榄叶水提取物对大鼠冠脉流量作用效果与丹参的类似,与生理盐水空白组比较差异有统计学意义,具有稳定和增加冠脉流量作用,给药后前6 min表现为加强心肌收缩力作用,而后均逐渐减弱恢复。心率在整个过程中持续下降,且下降速率快。结论乌榄叶水提取物对冠脉流量和心肌收缩力具有先增加后减少至给药前状态的双向作用,并有较快、较强的慢心率作用。结果提示乌榄叶可能有利于降低心脏耗氧量,维持心功能,起保护心肌的作用。     

乌菊降压丸药效学实验

目的 :对乌菊降压丸的药理作用进行实验研究。方法 :以正常血压大鼠和自发性高血压大鼠 (SHR )的血压和心率为动物模型 ,观察乌菊降压丸的药效作用。空白对照组给予相应量的0 5 %羧甲基纤维素钠 ;阳性对照组给予牛黄降压丸2g/kg;实验组给予乌菊降压丸 ,高、中、低剂量分别为1 2、0 6、0 2g/kg。灌胃给药 ,qd ,连续15d。分别观察并记录给药后10、20、30、45、60、90、120、240min时的血压和心率变化。结果 :乌菊降压丸高、中剂量对SHR分别在20、30min起效 ,血压开始下降 ,心率开始减慢 ,分别维持3h和1h ,4h和2h恢复原来水平。结论 :乌菊降压丸对正常血压大鼠的血压和心率无明显影响 (P>0 05) ,但有一定降低趋势 ;对SHR连续给药15d后具有明显降压作用和减慢心率的作用 (P<0 05) ;高剂量组有较好的降压效果     

乌榄果对动脉粥样硬化的干预作用

目的 研究乌榄果对载脂蛋白E基因敲除(Apolipoprotein-E knockout,ApoE-/-)小鼠脂质代谢的调控作用及动脉粥样硬化的干预作用.方法 将雄性ApoE-/-小鼠随机分成空白组、模型组、阿伐他汀钙组、乌榄果组.空白组:基础饲料+生理盐水,模型组:高脂饲料+生理盐水,阿伐他汀钙组:高脂饲料+阿伐他汀钙,乌榄果组:高脂饲料+乌榄果水提取物.4周后,乙醚麻醉取血,颈椎脱臼处死取材.检测血清中总胆固醇(TC)、总三酰甘油(TG)、高密度脂蛋白胆固醇(HDL-C)、低密度脂蛋白胆固醇(LDL-C);对胸腹主动脉纵切面油红O染色,测量红色斑块面积占比.结果 乌榄果组的AI(TC/HDL)、TG/HDL及LDL/HDL均低于模型组(均P＜0.05)和阿伐他汀钙组(均P＜0.05),模型组高于阿伐他汀钙组(均P＜ 0.05),乌榄果组的动脉斑块比值小于模型组(P＜0.01),模型组的动脉斑块比值大于阿伐他汀钙组(p＜0.01).结论 乌榄果对动脉粥样硬化有一定的干预作用,其机制可能与其抗氧自南基及降脂的作用有关.     

纵条矶海葵对高血压大鼠的降压作用

采用监测大鼠颈动脉血压、心电图和呼吸、观察纵条矶海葵提取物对自发性高大鼠及不同因素所致正常大鼠血压变化的影响，以探讨其抗高血压作用。结果显示，纵条矶海葵对正常大鼠及高血压大鼠均有一定的降低血压效应，对心率无明显影响，其降压作用有量效关系，未见有快速耐受现象，不影响肾上腺素、苯肾小腺素、血管紧张素Ⅱ及垂体后叶素对大鼠血压的反应性。提示纵条矾海葵有抗血压作用，且降压时肯反射性增快心率、其降太效应与直接     

紫荆叶与紫荆皮消炎镇痛作用比较

目的:研究紫荆叶与紫荆皮水提物和醇提物的消炎镇痛作用。方法:分别利用小鼠扭体法和二甲苯耳胀法研究紫荆叶与紫荆皮的消炎镇痛作用。结果:紫荆皮较紫荆叶的镇痛效果较好,不同剂量组差异均有显著性(P<0.01,P<0.05);紫荆皮与叶均有消炎作用,且紫荆皮效果较紫荆叶明显(P<0.01,P<0.05)。紫荆叶醇提物较水提物具有更加明显的镇痛消炎作用,而紫荆皮水提物较醇提物镇痛消炎作用显著。结论:紫荆皮较紫荆叶消炎镇痛作用显著,且不同溶剂提取物作用不同。     

石蒜伦碱对大鼠与犬的血压影响及对大鼠降压作用的快速耐受性及其作用机理

作者曾发现给成巴比妥钠麻醉的大鼠静脉注射石蒜伦碱(lycorenine),能使血压下降、心率减慢,重复给药可致快迅耐受。在此基础上,作者用正常大鼠、高血压大鼠和正常犬比较研究了石蒜伦碱及其类似物的降压作用,探讨其降压作用及产生快速耐受的作用机理。     

决芦降压口服液治疗原发性高血压的实验研究

目的探讨决芦降压口服液通腑滋阴泄肝的药效学依据。方法Wistar(30只,分大、小剂量组与对照组各10只)及高血压模型大鼠(10只)分别给予决芦降压口服液1.5ml/100g体重,用大鼠血压心率仪测定大鼠尾动脉收缩压及心率,观察给药前及给药后血压及心率的变化。结果给予决芦降压口服液后,正常大鼠及高血压模型大鼠血压均明显降低,同时高血压模型大鼠心率减慢。结论决芦降压口服液降低大鼠血压及心率可能是通腑滋阴泄肝的药效学基础。     

Effects of verapamil, nifedipine and flunarizine on haemodynamics and regional blood flows in pentobarbitone-anaesthetized rats

Representative calcium antagonists from proposed class I (nifedipine), class II (verapamil) and class III (flunarizine) have been examined for effects on blood pressure, heart rate, ventricular pressures, ECG, cardiac output and regional blood flow in pentobarbitone-anaesthetized rats. Flow was measured by the microsphere technique. Low and high infusion rates of each drug were chosen to decrease mean arterial pressure by 25 and 40 mmHg, respectively. At equi-depressor infusion rates, all drugs equally decreased total peripheral resistance and slightly increased cardiac output and stroke volume. Heart rate was decreased by verapamil and flunarizine, but increased by nifedipine. Verapamil markedly decreased dP/dtmax of ventricular pressure and prolonged the PR-interval. Flunarizine was similar. Nifedipine decreased dP/dtmax and had no effect on the PR-interval of the ECG. Similar effects on regional blood flow were seen with the three drugs; flow to lungs, heart, liver, skeletal muscle and stomach increased. Correction for blood pressure changes, i.e. conductance, showed that vasodilatation occurred in all regions, with all drugs, except for the skin. Therefore, representatives from three sub-classes of calcium antagonists had similar effects on blood flow but different effects on the heart.     

Central inhibitory effect of alpha-methyldopa on blood pressure, heart rate and body temperature of renal hypertensive rats.

The central inhibitory effect of alpha-methyldopa on blood pressure, heart rate and body temperature was studied in conscious renal hypertensive rats. Systemic administration of alpha-methyldopa decreased mean arterial blood pressure and body temperature and caused a short lasting increase in heart rate followed by a long lasting decrease. Inhibition of central decarboxylase activity prevented the decrease in blood pressure, heart rate and body temperature but not the initial increase in heart rate. Inhibition of peripheral decarboxylase activity blocked the increase in heart rate and partially reduced the decrease in heart rate and body temperature but did not affect the decrease in blood pressure. Alpha-Methyldopa also decreased blood pressure at an ambient temperature of 30 degrees C, but the decrease of body temperature was absent and the heart rate remained elevated for 7 hr. Similar results were obtained in normotensive rats. The decrease in heart rate was correlated with the decrease in body temperature in normotensive and renal hypertensive rats. These findings suggest that in the renal hypertensive rat the decrease in blood pressure and in body temperature depends on a central action of alpha-methyldopa metabolites.     

NORMOTENSIVE WISTAR RATS DIFFER FROM SPONTANEOUSLY HYPERTENSIVE AND RENAL HYPERTENSIVE RATS IN THEIR CARDIOVASCULAR RESPONSES TO OPIOID AGONISTS

1. The effects of three opioid receptor agonists on the blood pressure and heart rate of anaesthetized normotensive, spontaneously hypertensive and renal hypertensive rats were measured. 2. Mu agonist morphiceptin i.c.v. induced a pressor response and increase in heart rate in hypertensive rats, but hypotension in normotensive rats. After intravenous (i.v.) injection, morphiceptin produced a hypotensive response in all three groups of rats. 3. In contrast, the delta agonist DTLET i.c.v. decreased blood pressure and heart rate in hypertensive rats, but increased both pressure and beat rate in normotensive rats. After i.v. injections DTLET produced a hypertensive response and increase in heart rate in all groups of rats. 4. Kappa agonist U-50, 488H given i.c.v. induced effects similar to morphiceptin: an increase in blood pressure and heart rate in hypertensive and a decrease in normotensive rats. After i.v. injections U-50, 488H produced decreases in blood pressure and heart rate in all treated groups of rats. 5. Pretreatment with naloxone antagonized the activity of morphiceptin but prevented only the stimulating effect of DTLET in normotensive rats. Cardiovascular actions of U-50, 488H were not blocked by naloxone. 6. The results suggest that opioid agonists exert similar changes in cardiovascular function at central and peripheral sites in both models of experimental hypertension and these effects are different in normotensive rats.     

杨桃根醇提物对正常大鼠血压的影响

目的 研究杨桃根Averrhoa carambola root醇提物对正常大鼠血压的影响.方法 40只正常大鼠随机均分为5组:阳性对照组、正常对照组及杨桃根醇提物高、中、低剂量组.大鼠麻醉后以颈总动脉插管法连接心功能分析系统,待颈动脉血压稳定10 min后,测定给药前和十二指肠给药后30、60、90、120、150、180、210、240 min时大鼠的心率、收缩压、舒张压和平均动脉压.结果 杨桃根醇提物高剂量组大鼠的收缩压、舒张压、平均压分别于给药后60 min(由119.06±11.45 mmHg降至112.58±12.27 mmHg)、60 min(由110.91 ±9.83 mmHg降至95.44±14.82 mmHg)、90 min(由115.94±12.92 mmHg降至94.58±12.23 mmHg)开始降低;中剂量组大鼠的收缩压、舒张压、平均压分别于给药后150 min(由122.01±13.52 mmHg降至100.87 ± 15.04 mmHg)、90 min(由110.88 ± 13.75 mmHg降至89.52±17.91 mmHg)、90 min(由115.39±11.61 mmHg降至99.72±12.67 mmHg)开始降低.杨桃根醇提物对正常大鼠的心率无明显影响.结论 杨桃根醇提物能降低正常大鼠的血压.     

Acute effects of a sarin-like organophosphorus agent,bis(isopropyl methyl)phosphonate,on cardiovascular parameters in anaesthetized,artificially ventilated rats

The organophosphorus compound sarin irreversibly inhibits acetylcholinesterase. We examined the acute cardiovascular effects of a sarin-like organophosphorus agent, bis(isopropyl methyl)phosphonate (BIMP), in anaesthetized, artificially ventilated rats. Intravenous administration of BIMP (0.8 mg/kg; the LD50 value) induced a long-lasting increase in blood pressure and tended to increase heart rate. In rats pretreated with the non-selective muscarinic-receptor antagonist atropine, BIMP significantly increased both heart rate and blood pressure. In atropine-treated rats, hexamethonium (antagonist of ganglionic nicotinic receptors) greatly attenuated the BIMP-induced increase in blood pressure without changing the BIMP-induced increase in heart rate. In rats treated with atropine plus hexamethonium, intravenous phentolamine (non-selective α-adrenergic receptor antagonist) plus propranolol (non-selective β-adrenergic receptor antagonist) completely blocked the BIMP-induced increases in blood pressure and heart rate. In atropine-treated rats, the reversible acetylcholinesterase inhibitor neostigmine (1 mg/kg) induced a transient increase in blood pressure, but had no effect on heart rate. These results suggest that in anaesthetized rats, BIMP induces powerful stimulation of sympathetic as well as parasympathetic nerves and thereby modulates heart rate and blood pressure. They may also indicate that an action independent of acetylcholinesterase inhibition contributes to the acute cardiovascular responses induced by BIMP.