Editing Psychopharmacology (section)

==Chemical signaling==

===Neurotransmitters===
Psychoactive drugs exert their sensory and behavioral effects almost entirely by acting on [[neurotransmitter]]s and by modifying one or more aspects of synaptic transmission. Neurotransmitters can be viewed as chemicals through which [[neuron]]s primarily communicate; psychoactive drugs affect the mind by altering this communication. Drugs may act by 1) serving as a [[precursor (chemistry)|precursor]] to a neurotransmitter; 2) inhibiting neurotransmitter synthesis; 3) preventing storage of neurotransmitters in the pre[[synaptic vesicle]]; 4) stimulating or inhibiting neurotransmitter release; 5) stimulating or blocking post-synaptic receptors; 6) stimulating [[autoreceptor]]s, inhibiting neurotransmitter release; 7) blocking autoreceptors, increasing neurotransmitter release; 8) inhibiting neurotransmission breakdown; or 9) blocking neurotransmitter [[reuptake]] by the presynaptic neuron.<ref name=Psychopharm />

===Hormones===
The other central method through which drugs act is by affecting communications between cells through [[hormone]]s. Neurotransmitters can usually only travel a microscopic distance before reaching their target at the other side of the [[synaptic cleft]], while hormones can travel long distances before reaching target cells anywhere in the body. Thus, the [[endocrine system]] is a critical focus of psychopharmacology because 1) drugs can alter the secretion of many hormones; 2) hormones may alter the behavioral responses to drugs; 3) hormones themselves sometimes have psychoactive properties; and 4) the secretion of some hormones, especially those dependent on the [[pituitary gland]], is controlled by neurotransmitter systems in the brain.<ref name=Psychopharm />