Investigation of Nicotine Seeking Behavior in Current Smokers
Condition: Cigarette Smoking
Study type: Interventional
Phase: Phase 1

Summary: 
      In this study, 21 non-treatment-seeking cigarette smokers were recruited to investigate the
      effects of acute stress on brain function and nicotine seeking/self-administration behavior.
    

Detailed description: 
      Non-treatment-seeking cigarette smoking individuals were recruited from the Detroit, MI area.
      Individuals were screened for cardiovascular, neurological, and psychiatric
      contraindications. 21 healthy smokers completed two oral pre-treatment experimental sessions
      (on separate non-consecutive days) in randomized order under double-blind conditions: placebo
      (lactose) and stress (54mg yohimbine and 10mg hydrocortisone). Yohimbine + hydrocortisone
      elicit a neurochemical and physiological response that mimics a 'natural' stressor. Placebo
      and stress sessions were identical and started at 11am. Upon arrival, subject sobriety was
      confirmed with expired breath alcohol measurement (<.02%). At 11:30am, each subject smoked 6
      cigarette puffs (preferred brand; provided by study) over 5 minutes to control for recent
      nicotine exposure. Throughout each experimental session, subjects periodically completed
      self-reported measures of cigarette craving, nicotine withdrawal symptoms, affect, and
      anxiety, and vital signs were measured. Subjects self-administered (swallowed) oral doses of
      yohimbine (or placebo) at 11:45am and hydrocortisone (or placebo) at 12:15pm. At 1pm,
      subjects completed a 60-min neuroimaging scan which included: 1) T1-weighted structural scan,
      2) proton functional magnetic resonance spectroscopy (fMRS) acquisition from the left
      prefrontal cortex during a letter 2-back working memory paradigm, and 3) functional magnetic
      resonance imaging (fMRI) acquisition during an N-back paradigm yoked with cigarette cues. At
      2:30pm, subjects completed an 11-trial choice progressive ratio task in which they could earn
      cigarette puffs (preferred brand; provided by study) or money. At 3pm, subjects
      self-administered earned cigarette puffs (video monitored). Subjects remained on site until
      4pm discharge.
    

Intervention name(s): Yohimbine Hydrochloride; Hydrocortisone; Lactose Monohydrate Powder
Intervention type(s): Drug; Drug; Drug
Intervention description(s): 54mg of yohimbine powder was encapsulated in a generic opaque capsule and swallowed with water.; 10mg hydrocortisone was encapsulated in a generic opaque capsule and swallowed with water.; Lactose powder was encapsulated in generic opaque capsules identical to those used during the acute stress session. Lactose doses weighed the same as the acute stress session doses (54mg and 10mg, respectively).
Other intervention name(s): YOH; HYD; Placebo
Intervention MeSH terms: Hydrocortisone; Yohimbine
Allocation: Randomized
Intervention model: Single Group Assignment
Intervention model description: Double-blind, placebo-controlled, and randomized cross-over study design. Each subject completed both the placebo and acute stress experimental sessions.
Masking: Double (Participant, Investigator)
Primary purpose: Basic Science
Keywords: cigarette smoking; acute stress; executive function; craving; nicotine seeking; relapse; excitatory neural activity; glutamate; negative affect