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人体中咖啡因和尼古丁之间的心血管相互作用在一项安慰剂对照双盲随机的设计中,作者们对10名健康志愿者在基线状况下和在身心紧张(站立和心算)期间研究了咖啡因(静注250mg)和尼古丁(4mg口香糖)之间的心血管相互作用.单用咖啡因可使血压明显升高伴心率减缓.而单用尼古丁则即使血压升高也使心率增速.合用二药可使收缩期和舒张期血压分别上升10.8±20mmHg和12.4±1.9mmHg.这种加压效应与咖啡因和尼古丁对血压的计算出来的相加效应(经测定分别为12.9±2.0mmHg和14.2±2.1mmHg)并无明显差异.当比较合用二药的结果与二药单用的结果之和时,心率和前臂血流也显示出类似的效应.在身体处于紧张(站立)的时候,血压、心率和血浆儿茶酚胺浓度在安慰剂试验中均见上升.在合用二药后与二药单用后之和相比,这种对站立所产生的加压效应,前者明显低于后者(合用二药对二药单用之和:舒张压,24.7±1.9mmHg对35.2±2.6mmHg[P<0.01];平均动脉压,22.1±2.0mmHg对28.6±1.6mmHg[P<0.05].血浆儿茶酚胺反应在合用二药和二药单用时的和之间没有区别.在心算期间、血压、心率和前臂血流在安慰剂试验中可见上升.与二药单用之和相比,合用二药可使前臂对精神紧张所产生的血管舒张效应减弱(合用二药对二药单用之和:前臂血流.-0.1±0.3mL/
Cardiovascular Interactions Between Caffeine and Nicotine in the Human In a placebo-controlled, double-blind, randomized design, the authors studied 10 healthy volunteers during baseline conditions and during physical and mental stress (standing and mental arithmetic) Cardiovascular interactions between caffeine (250 mg intravenously) and nicotine (4 mg chewing gum) significantly increased blood pressure with slowing heart rate with caffeine alone, while heart rate increased even with elevated blood pressure. The combined use of two drugs increased systolic and diastolic blood pressure by 10.8 ± 20 mmHg and 12.4 ± 1.9 mmHg, respectively. This additive effect was additive with the calculated additive effect of caffeine and nicotine on blood pressure (measured as 12.9 ± 2.0 mmHg And 14.2 ± 2.1 mmHg.) Heart rate and forearm blood flow also showed similar effects when compared with the sum of the combined two-drug results and the two-drug-only results.While the body is stressed (standing) , Blood pressure, heart rate and plasma catecholamine concentrations were all increased in the placebo test.Compared with the sum of the two drugs alone after the combination of the two drugs, the pressure effect on the standing, the former was significantly lower than the latter (Combination of two drugs on two drugs The sum of: diastolic blood pressure, 24.7 ± 1.9mmHg vs 35.2 ± 2.6mmHg [P <0.01]; mean arterial pressure, 22.1 ± 2.0mmHg versus 28.6 ± 1.6mmHg [P <0.05] There was no difference between the single and the single use of drugs during the mental arithmetic period, blood pressure, heart rate and forearm blood flow can be seen in the placebo test increased compared with the sum of the two drugs alone, combined with two drugs can make the forearm on mental stress Of the vasodilator effect weakened (combination of two drugs on the two drugs and the sum of: forearm blood flow-0.1 ± 0.3mL /