220 likes | 536 Views
Nicotine and Caffeine Chapter 12. Leaves of the Nicotiana tabacum plant. Nicotine. History. Nicotine. Routes of Administration Inhalation Chewing Snorting Transdermal. Nicotine. Metabolism of Nicotine liver converts nicotine into metabolites cotinine half life: 2 hrs
E N D
Nicotine and Caffeine Chapter 12
Leaves of the Nicotiana tabacum plant Nicotine History
Nicotine Routes of Administration Inhalation Chewing Snorting Transdermal
Nicotine • Metabolism of Nicotine • liver converts nicotine into metabolites • cotinine • half life: 2 hrs • acute tolerance
Nicotine Site of action for nicotine • Nicotinic cholinergic receptors (nAChR) • Basic functions of different receptors: • Open Na+ channels increase firing potential • Allows Ca2+ into cell 2nd messengers • Enhances NT release (presynaptic)
Nicotine Site of action for nicotine • Nicotinic cholinergic receptors (nAChR) • Locations of receptors • Neuromuscular junction at muscles • PNS • CNS • Postsynaptic • Presynaptic membranes of other NT neurons
Changes in cognitive functionNicotine-induced reduction of reaction time in a rapid visual information processing task Nicotine
Nicotine Activation of mesolimbic dopamine system Time
Nicotine Activation of mesolimbic dopamine systemNicotine self-administration in rats first exposed to the drug during adolescence vs. adulthood
Nicotine Changes in mood • Smokers • Non-smokers
Nicotine Factors other than NicotineWhole-body PET scans illustrating reduced MAO-B activity
Nicotine Tolerance - acute - chronic Withdrawal symptoms • Decrease heart rate and blood pressure • Irritability • Hunger • Sleep disturbances • GI complaints • Headache • Impairment of concentration
Nicotine Effects of smoking on general health Increased risk for: • Cancer • Cardiovascular disease • Emphysema • Chronic bronchitis • Decreased birth weight in infants for mothers who smoked
Nicotine Why do people smoke? • Nicotine resource model • Deprivation reversal model • Positive reinforcement (DA reward system) • Substances other than nicotine • Genetic factors?
Nicotine Treatment of nicotine dependence
http://scienceblogs.com/retrospectacle/upload/2007/04/caffeine.jpghttp://scienceblogs.com/retrospectacle/upload/2007/04/caffeine.jpg http://www.caffeinemedia.com.au/images/Caffeine-Holding-Page_03.jpg
Caffeine Absorption and Metabolism
Caffeine Mechanism of action • Adenosine antagonist
Caffeine Withdrawal and ToleranceTime course of caffeine withdrawal in regular users (Part 1)
Caffeine Withdrawal and ToleranceTime course of caffeine withdrawal in regular users (Part 2)
Caffeine Withdrawal and ToleranceTime course of caffeine withdrawal in regular users (Part 4)