dopamine receptors are located in the reward pathway of the brain.
dopamine receptors are located in the reward pathway of the brain.
where are the dopamine receptors located in the brain?
reward pathway
dopaminergic means "related to dopamine" (literally, "working on dopamine"), dopamine being a common neurotransmitter. dopaminergic substances or actions increase dopamine-related activity in the brain. dopaminergic brain structures facilitate dopamine-related activity. for example, certain proteins such as the dopamine transporter (dat), vesicular monoamine transporter 2 (vmat), and dopamine receptors can be classified as dopaminergic, and neurons that synthesize or contain dopamine and synapses with dopamine receptors in them may also be labeled as "dopaminergic". enzymes that regulate the biosynthesis or metabolism of dopamine such as aromatic l-amino acid decarboxylase or dopa decarboxylase, monoamine oxidase (mao), and catechol "o"-methyl transferase (comt) may be referred to as "dopaminergic" as well. also, any endogenous or exogenous chemical substance that acts to affect dopamine receptors or dopamine release through indirect actions (for example, on neurons that synapse onto neurons that release dopamine or express dopamine receptors) can also be said to have "dopaminergic" effects, two prominent examples being opioids, which enhance dopamine release indirectly in the reward pathways, and some substituted amphetamines, which enhance dopamine release directly by binding to and inhibiting vmat.
dopaminergic
dopamine exerts its effects by binding to and activating cell surface receptors. in humans, dopamine has a high binding affinity at dopamine receptors and human trace amine-associated receptor 1 (htaar1). in mammals, five subtypes of dopamine receptors have been identified, labeled from d1 to d5. all of them function as metabotropic, g protein-coupled receptors, meaning that they exert their effects via a complex second messenger system. these receptors can be divided into two families, known as d1-like and d2-like. for receptors located on neurons in the nervous system, the ultimate effect of d1-like activation (d1 and d5) can be excitation (via opening of sodium channels) or inhibition (via opening of potassium channels); the ultimate effect of d2-like activation (d2, d3, and d4) is usually inhibition of the target neuron. consequently, it is incorrect to describe dopamine itself as either excitatory or inhibitory: its effect on a target neuron depends on which types of receptors are present on the membrane of that neuron and on the internal responses of that neuron to the second messenger camp. d1 receptors are the most numerous dopamine receptors in the human nervous system; d2 receptors are next; d3, d4, and d5 receptors are present at significantly lower levels.
dopamine