The psychopharmacology of D-1 dopamine receptors

Drugs affecting neurotransmitter synthesis can impact the adrenergic neuron and the synthesis of neurotransmitters. For example, α-methyltyrosine and carbidopa target specific enzymes involved in catecholamine synthesis. α-methyltyrosine inhibits the enzyme tyrosine hydroxylase, which converts tyrosine into dopamine. By blocking this enzyme, α-methyltyrosine reduces dopamine production and other catecholamines. Carbidopa, on the other hand, inhibits the enzyme dopa decarboxylase, which converts...

Antipsychotic drugs are classified into first-generation (typical) drugs including phenothiazines; and second-generation (atypical) drugs. Chlorpromazine hydrochloride (Thorazine), a phenothiazine derivative, broadly impacts the central, autonomic, and endocrine systems. This drug, along with typical agents like haloperidol (Haldol), primarily works by antagonizing D2 receptors, thus reducing dopaminergic neurotransmission. However, typical antipsychotics can cause side effects such as sedation...

Indirect-acting adrenergic agonists potentiate the effects of endogenous catecholamines through different mechanisms without directly binding to adrenoceptors.
One mechanism involves depleting stored catecholamines by displacing them from synaptic vesicles. These agents, known as "displacers," are transported into vesicles at the expense of noradrenaline. Examples include amphetamine and tyramine, which lack a catechol moiety, resulting in prolonged action, improved oral bioavailability, and...

Prokinetic agents are specialized medications that stimulate gastrointestinal (GI) motility, promoting food movement through the GI tract. Dopamine, an inhibitory neurotransmitter, plays a significant role in this process, reducing GI motility and indirectly controlling the speed of digestion. Dopamine receptor antagonists, such as metoclopramide and domperidone, offer a unique advantage as prokinetic agents. By blocking the dopamine receptors, these drugs increase GI motility, improving food...

Schizophrenia is a neurodevelopmental disorder whose origins are rooted in complex genetic components. Despite our burgeoning understanding, the pathophysiology of this disorder remains incompletely deciphered.
Researchers have identified genetic factors that increase susceptibility to schizophrenia, underscoring the intricate interplay between genetics and environment in disease development. At the core of schizophrenia's pathophysiology is excessive dopaminergic neurotransmission within the...

Certain drugs can affect how neurotransmitters called catecholamines, are released or taken back up in the adrenergic neuron. They can have different effects on the body's sympathetic transmission. Reserpine, a natural compound found in the Rauwolfia shrub, blocks a transporter called vesicular monoamine transporter (VMAT), which leads to a buildup of catecholamines in the cell and reduces sympathetic transmission. Another drug called guanethidine works in multiple ways, including blocking...