Nicotine Related Brain Activity: The Influence of Smoking History and Blood Nicotine Levels, an Exploratory Study
试验速览
- 阶段
- 不适用
- 状态
- 已完成
- 入组人数
- 15
- 试验地点
- 1
- 主要终点
- Peak Nicotine Levels
研究概览
简要总结
In this study, we sought to explore brain activity in nicotine-dependent men in response to acute intravenous nicotine using pharmacological magnetic resonance imaging (phMRI).
详细描述
phMRI was used to evaluate brain activity in response to 1.5 mg/70 kg intravenous nicotine or saline. The nicotine and saline were administered on different visits. The time courses of individual subjects' nicotine levels were used as regressors to assess neural activity relating to the infusions. The influence of Smoking history and physiological measures on the response to nicotine were also investigated.
研究设计
- 研究类型
- Interventional
- 分配方式
- Randomized
- 干预模型
- Crossover
- 主要目的
- Other
- 盲法
- Double (Participant, Investigator)
入排标准
- 年龄范围
- 18 Years 至 40 Years（Adult）
- 性别
- All
- 接受健康志愿者
- 是
入选标准
- •Men and women between the ages of 18 and 40 who currently smoke at least 15 cigarettes every day, and who fulfill DSM-IV diagnostic criteria for nicotine dependence will be eligible for participation.
- •No evidence of clinically significant disease based upon complete medical history and physical examination by a qualified physician.
- •Absence of DSM-IV Axis I Disorders other than nicotine dependence (305.10) as measured by the Structured Clinical Interview (SCID).
- •Routine laboratory blood tests including complete blood count, electrolytes, BUN and creatinine, liver function tests, hepatitis panel and urinalysis will be performed. Laboratory parameters must be within the normal range. HBsAg must be negative but subjects who have hepatitis serology consistent with previous exposure to Hepatitis A, Hepatitis B, or Hepatitis C, but who do not have clinical and biochemical evidence of acute infection, will be acceptable.
- •Hematocrit levels ≥ 39% for males and ≥ 35% for females.
- •Serum pregnancy test (hCG beta subunit) results must be negative within 24 hrs of the study day.
- •Normal ECG.
- •A Body Mass Index (BMI-ratio of weight (W) to height (H) squared; W/H2=kg/m2) of between 18.0 and 27.0 for women and 21.4 to 29 for men.
- •Subjects must be able to read and understand instructions, as well as provide a valid informed consent.
排除标准
- •Participants with any lifetime DSM-IV Axis I disorder other than nicotine dependence.
- •Participants with clinically significant medical disorders.
- •Women who are pregnant as determined by laboratory testing for serum beta hCG.
- •Women who use hormonal contraceptive medications will not be accepted, because this would confound the hormonal measures.
- •Women with a mean BMI of outside the range 18.0-27.0 and men with a BMI outside the range 21.4-29.
- •Participants with ferromagnetic implants or other contraindications to fMRI
- •Cardiac pacemakers
- •Metal clips on blood vessels (also called stents)
- •Artificial heart valves
- •Artificial arms, hands, legs, etc.
- •Brain stimulator devices
- •Implanted drug pumps
- •Ear implants
- •Eye implants or known metal fragments in eyes
- •Exposure to shrapnel or metal filings (wounded in military combat, sheet metal workers, welders, and others)
- •Other metallic surgical hardware in vital areas
- •Certain tattoos with metallic ink
- •Transdermal patches (eg. Orthro Evra, Nicoderm CQ)
- •Metal IUD (s)
- •Participants who describe themselves as seeking treatment will not be selected but will be referred to local smoking cessation programs.
研究组 & 干预措施
Intravenous Nicotine (1.5 mg/70 kg)
Participants are given a siingle infusion of nicotine (1.5 mg/70 kg), administered over 1 minute into the antecubital vein 10 minutes into their MRI scans
干预措施: Intravenous Nicotine (Drug)
Saline - placebo
Participants are given physiological saline, administered over 1 minute into the antecubital vein 10 minutes into their MRI scans
干预措施: Saline - placebo (Other)
结局指标
主要结局
Peak Nicotine Levels
时间窗: 0, 2, 4, 6, 8, 10, 12, 14, 16, 20, 30 minutes post-infusion
Peak nicotine level in each participant
Number of Brain Regions With a Change in Brain Activity Relative to Saline
时间窗: 40 minutes after infusion
PhMRI analysis of the differential response of nicotine compared to the saline condition when analyzed with the nicotine time course. The main dependent variable in this study, Blood Oxygen Level Dependent (BOLD) measures of brain activity (via fMRI) data does not exist in a vacuum-it is always relative to another measure of brain activity, typically collected at rest or after a placebo injection. So we collected the data after the IV placebo injection alone and the IV nicotine injection alone, but then need applied mathematical CONTRASTS to the data. This procedure results in the brain activity maps.
次要结局
- Number of Brain Regions With a Change in Brain Activity Relative to Saline When Analyzed With the Nicotine Time Course Controlling for Smoking History(40 minutes after infusion)
- Number of Brain Regions With a Change in Brain Activity Relative to Saline When Analyzed With Smoking History Controlling for Nicotine(40 minutes after infusion)
- Final Nicotine Levels(30 minutes post-infusion)
研究者
Scott Lukas
Director, McLean Imaging Center
Mclean Hospital