PSYC62H3 Study Guide - Midterm Guide: Adenosine, Chemical Classification, Antibody
Document Summary
Psyc62-l5: mild stimulants nicotine & caffeine (ch7) Forms: cigarettes, cigars, hookah, chew, snuff, dipping tobacco, dissolvable tobacco. Nicotine tar adheres to tissues in the mouth, nose, throat, lungs and skin. Freebase form of nicotine best absorbs through mucous membranes in the mouth. Peak absorption is 7 min (cigarettes) to 25 min. (smokeless tobacco products) In liver, cyp-2a6 enzymes metabolize 80-90% of nicotine, producing the active metabolite cotinine. Chronic smokers have a 30% faster elimination rate of nicotine than nonsmokers. Nicotine is an agonist for cholinergic nicotinic receptors (nachrs) Channels close & cannot be opened even when agonist is bound. Receptors remain in inactivated state longer than an activated state. Also influences ach, glutamate, gaba, norepinephrine, 5-ht, vasopressin. Cardiovascular effects: increases in heart rate and blood pressure. Nicotine also reduces appetite in both non-tobacco users and long-term smokers. Reduced hand steadiness and hand tremor in non-tobacco users. Tolerance for these effects w/ tobacco users.
