Imaging the neurochemistry of nicotine actions: studies with positron emission tomography.

摘要: Although the effects of nicotine in brains laboratory animals have been investigated extensively, very little is known about its human brain. With positron emission tomography (PET), a non-invasive imaging technology that allows measurement concentration positron-labeled compounds are physiological and pharmacological relevance, it has become possible to investigate These studies shown fast pharmacokinetics brain, changes cerebral blood flow (CBF) brain metabolism, at least some these show acute tolerance. PET also that, addition nicotine, cigarettes possess other actions may contribute their reinforcing effects, inhibit monoamine oxidase (MAO) A B this inhibition recovers with cigarette discontinuation. receptors not yet imaged living primate high thalamus rate blockade by doses approximate plasma levels achieved humans when smoking cigarettes. However, further required determine receptor occupancies those for patch be therapeutically effective, measure half-life MAO mechanisms underlying inhibition, evaluate on neurotransmitter systems