<P> Drugs can influence behavior by altering neurotransmitter activity . For instance , drugs can decrease the rate of synthesis of neurotransmitters by affecting the synthetic enzyme ( s ) for that neurotransmitter . When neurotransmitter syntheses are blocked , the amount of neurotransmitters available for release becomes substantially lower , resulting in a decrease in neurotransmitter activity . Some drugs block or stimulate the release of specific neurotransmitters . Alternatively , drugs can prevent neurotransmitter storage in synaptic vesicles by causing the synaptic vesicle membranes to leak . Drugs that prevent a neurotransmitter from binding to its receptor are called receptor antagonists . For example , drugs used to treat patients with schizophrenia such as haloperidol , chlorpromazine , and clozapine are antagonists at receptors in the brain for dopamine . Other drugs act by binding to a receptor and mimicking the normal neurotransmitter . Such drugs are called receptor agonists . An example of a receptor agonist is Valium , a benzodiazepine that mimics effects of the endogenous neurotransmitter gamma - aminobutyric acid ( GABA ) to decrease anxiety . Other drugs interfere with the deactivation of a neurotransmitter after it has been released , thereby prolonging the action of a neurotransmitter . This can be accomplished by blocking re-uptake or inhibiting degradative enzymes . Lastly , drugs can also prevent an action potential from occurring , blocking neuronal activity throughout the central and peripheral nervous system . Drugs such as tetrodotoxin that block neural activity are typically lethal . </P>
<P> Drugs can influence behavior by altering neurotransmitter activity . For instance , drugs can decrease the rate of synthesis of neurotransmitters by affecting the synthetic enzyme ( s ) for that neurotransmitter . When neurotransmitter syntheses are blocked , the amount of neurotransmitters available for release becomes substantially lower , resulting in a decrease in neurotransmitter activity . Some drugs block or stimulate the release of specific neurotransmitters . Alternatively , drugs can prevent neurotransmitter storage in synaptic vesicles by causing the synaptic vesicle membranes to leak . Drugs that prevent a neurotransmitter from binding to its receptor are called receptor antagonists . For example , drugs used to treat patients with schizophrenia such as haloperidol , chlorpromazine , and clozapine are antagonists at receptors in the brain for dopamine . Other drugs act by binding to a receptor and mimicking the normal neurotransmitter . Such drugs are called receptor agonists . An example of a receptor agonist is Valium , a benzodiazepine that mimics effects of the endogenous neurotransmitter gamma - aminobutyric acid ( GABA ) to decrease anxiety . Other drugs interfere with the deactivation of a neurotransmitter after it has been released , thereby prolonging the action of a neurotransmitter . This can be accomplished by blocking re-uptake or inhibiting degradative enzymes . Lastly , drugs can also prevent an action potential from occurring , blocking neuronal activity throughout the central and peripheral nervous system . Drugs such as tetrodotoxin that block neural activity are typically lethal . </P>
which category of drugs includes many substances that are chemically similar to neurotransmitters
which category of drugs includes many substances that are chemically similar to neurotransmitters
receptor agonists
receptor agonists