Different physiological and behavioural effects of e-cigarette vapour and cigarette smoke in mice

Eur Neuropsychopharmacol. 2015 Oct;25(10):1775-86. doi: 10.1016/j.euroneuro.2015.06.010. Epub 2015 Jun 20.


Nicotine is the primary addictive substance in tobacco smoke and electronic cigarette (e-cig) vapour. Methodological limitations have made it difficult to compare the role of the nicotine and non-nicotine constituents of tobacco smoke. The aim of this study was to compare the effects of traditional cigarette smoke and e-cig vapour containing the same amount of nicotine in male BALB/c mice exposed to the smoke of 21 cigarettes or e-cig vapour containing 16.8 mg of nicotine delivered by means of a mechanical ventilator for three 30-min sessions/day for seven weeks. One hour after the last session, half of the animals were sacrificed for neurochemical analysis, and the others underwent mecamylamine-precipitated or spontaneous withdrawal for the purposes of behavioural analysis. Chronic intermittent non-contingent, second-hand exposure to cigarette smoke or e-cig vapour led to similar brain cotinine and nicotine levels, similar urine cotinine levels and the similar up-regulation of α4β2 nicotinic acetylcholine receptors in different brain areas, but had different effects on body weight, food intake, and the signs of mecamylamine-precipitated and spontaneous withdrawal episodic memory and emotional responses. The findings of this study demonstrate for the first time that e-cig vapour induces addiction-related neurochemical, physiological and behavioural alterations. The fact that inhaled cigarette smoke and e-cig vapour have partially different dependence-related effects indicates that compounds other than nicotine contribute to tobacco dependence.

Keywords: Cigarette smoke; Electronic cigarettes, mecamylamine-precipitated withdrawal; Nicotine; Nicotinic receptors; Spontaneous withdrawal.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Body Weight / drug effects
  • Brain / drug effects
  • Brain / metabolism
  • Cotinine / metabolism
  • Disease Models, Animal
  • Eating / drug effects
  • Electronic Nicotine Delivery Systems / adverse effects*
  • Emotions / drug effects
  • Male
  • Mecamylamine / pharmacology
  • Memory, Short-Term / drug effects
  • Mice, Inbred BALB C
  • Nicotine / administration & dosage
  • Nicotine / metabolism
  • Nicotinic Agonists / administration & dosage
  • Nicotinic Agonists / metabolism
  • Nicotinic Antagonists / pharmacology
  • Receptors, Nicotinic / metabolism
  • Respiration, Artificial
  • Spatial Memory / drug effects
  • Substance Withdrawal Syndrome / physiopathology
  • Substance Withdrawal Syndrome / psychology
  • Tobacco Smoke Pollution / adverse effects*
  • Tobacco Use Disorder / etiology
  • Tobacco Use Disorder / physiopathology*


  • Nicotinic Agonists
  • Nicotinic Antagonists
  • Receptors, Nicotinic
  • Tobacco Smoke Pollution
  • nicotinic receptor alpha4beta2
  • Mecamylamine
  • Nicotine
  • Cotinine