The Effects of Propofol and Thiopental on Nitric Oxide Production and Release in Erythrocytes
试验速览
- 阶段
- 不适用
- 状态
- 已完成
- 发起方
- 入组人数
- 12
- 试验地点
- 1
- 主要终点
- The effects of thiopental and propofol on erythrocyte NO synthase activity and erythrocyte-mediated NO release.
研究概览
简要总结
Hypotension is frequently encountered during the use of these commonly used intravenous anaesthetic agents (thiopental and propofol). This is thought to be a consequence of their effects on the sympathetic nervous system, myocardial contractility or vascular tone. However, propofol causes a greater fall in systemic arterial blood pressure than any other drug used for induction of anaesthesia. Propofol causes profound vasodilation, whereas its myocardial depressant effect is not clear. The vasodilatation occurs in both arterial and venous systems. The decrease in systemic arterial blood pressure after thiopental induction is mainly due to peripheral vasodilatation caused by depression of the medullary vasomotor centre and inhibition of the sympathetic nervous system. However, how this peripheral vasodilator effect occurs after both drugs and which mediators accompany it have not yet been fully elucidated. In previous studies, it has been emphasised that systemic vasodilation may be related with increased formation of nitric oxide (NO), a small gaseous and lipophilic molecule which plays an important role in the regulation of vascular homeostasis and haemoregulation. It is important to elucidate the mechanisms that may mediate thiopental- and propofol-mediated vasodilatation in future studies in order to help the methods and treatments that can be developed to prevent hypotension caused by these drugs, which are widely used in clinical practice. Therefore, the aim of this study was to investigate the effects of thiopental and profol on erythrocyte NO synthase activity and erythrocyte-mediated NO release.
详细描述
Male patients aged 18-45 years with ASA (American Society of Anaesthesiologists) class I (normal, healthy person without any disease or systemic problem other than surgical pathology that does not cause a systemic disorder) who applied to the anaesthesiology and reanimation clinic outpatient clinic for preoperative preparation were planned to be included in the study. Women, patients with ASA class >1, patients with known thiopental/propofol allergy and patients outside the age range of 18-45 years were excluded from the study. Venous blood samples will be taken from the patients included in the study and incubated with thiopental and propofol (dose: 100, 250, 500 and 1000µM) after appropriate procedures in the laboratory environment. . After incubation, all resuspensions will be subjected to flow cytometric analysis to evaluate erythrocyte NO synthase activity and erythrocyte-mediated NO release.All patients included in the study will be informed and their written and verbal consent will be obtained.
研究设计
- 研究类型
- Interventional
- 分配方式
- Non Randomized
- 干预模型
- Parallel
- 主要目的
- Other
- 盲法
- Single (Participant)
入排标准
- 年龄范围
- 18 Years 至 45 Years（Adult）
- 性别
- Male
- 接受健康志愿者
- 是
入选标准
- •Male patients
- •Aged 18-45 years
- •ASA (American Society of Anaesthesiologists) class I (normal, healthy person without any disease or systemic problem other than surgical pathology that does not cause a systemic disorder)
排除标准
- •Women patients
- •ASA class >1
- •Patients with known thiopental/propofol allergy
- •Patients outside the age range of 18-45 years
研究组 & 干预措施
Thiopental
Venous blood samples will be taken from the patients included in the study and incubated with thiopental (dose: 100, 250, 500 and 1000µM) after appropriate procedures in the laboratory environment. . After incubation, all resuspensions will be subjected to flow cytometric analysis to evaluate erythrocyte NO synthase activity and erythrocyte-mediated NO release.
干预措施: Thiopental (Drug)
Propofol
Venous blood samples will be taken from the patients included in the study and incubated with propofol (dose: 100, 250, 500 and 1000µM) after appropriate procedures in the laboratory environment. . After incubation, all resuspensions will be subjected to flow cytometric analysis to evaluate erythrocyte NO synthase activity and erythrocyte-mediated NO release.
干预措施: Propofol (Drug)
结局指标
主要结局
The effects of thiopental and propofol on erythrocyte NO synthase activity and erythrocyte-mediated NO release.
时间窗: 120 days
Blood samples will be taken from healthy human volunteers aged 25-45 years. Measurements will be performed using the fluorescent NO probe 4-amino-5-methylamino-20,70-difluorofluorescein diacetate. Propofol and thiopental will be added to the suspensions at doses of 100, 250, 500 and 1000 µM and incubated for 30 minutes. We will repeate these experiments in the presence of L-NAME, a non-specific nitric oxide synthase inhibitor. The nitrite/nitrate concentration will be measured in the supernatant of the erythrocyte suspensions after centrifugation.Intracellular calcium measurements will also be made during propofol and thiopental experiments. Fluo-4 calcium dye will be added to the medium and flow cytometric measurements will be repeated.
次要结局
- The effects of thiopental and propofol on erythrocyte haemorheology(120 days)
研究者
Melike Cengiz
MD,Professor Doctor
Akdeniz University