Reinoud Maex's journal club session, where he will summerise the work he did in Paris, which was sponsored by Targacept: a pharmaceutical company which specialised in nicotinic compounds.
Nicotine and nicotinic compounds bind to acetylcholine receptors, but, surprisingly, it is largely unknown whether they act by activating or by desensitising (= inactivating) these receptors.
We simulated a simple circuit of dopaminergic and gaba-ergic neurons, each of them expressing different subtypes of nicotinic receptors.
Our main conclusion was that many nicotinic compounds act by desensitising their receptors. We also formulated a new hypothesis on nicotine addiction. We propose that smoking in addicted people my be a form of self-medication: by desensitising the nicotinic receptors on GABAergic neurons, nicotine disinhibits the dopamine-neurons and restores their physiological response to acetylcholine.