Hypodopaminergic traits: what it is and how it occurs
Hypodopaminergic refers to significantly reduced levels of dopamine as opposed to baseline (normal) levels.
One of the causes behind hypodopaminergic traits is the presence of the DRD2 A1 allele, that disrupts the formation of dopamine receptors. With less dopamine receptors, the response to dopamine diminishes - leading to hypodopaminergic conditions.
The DRD2 A1 allele further can lead to hypodopaminergic conditions by disrupting DOPA L-amino acid decarboxylase activity, which is responsible for synthesizing dopamine in the first place. If less dopamine is synthesized, there will be less dopamine released from neurons upon stimulation.
Alternatively, it can result from a higher extracellular K+ ion concentration, resulting in lower dopaminergic release upon stimulation. Essentially, the higher K+ ion concentration lowers the resting membrane potential of the cell, and thus increased stimulation is necessitated to produce the same quantity of dopamine that a normal cell would produce.
Another potential cause is impaired storage of dopamine in cell vesicles. As such, dopamine could be lost by leaking into the cytoplasm, yielding less dopamine for neurotransmission.
Hypodopaminergic traits often result in symptoms of Attention Deficit Hyperactive Disorder (ADHD), and negative schizophrenic symptoms, shown below.
It also promotes more risk-taking behavior, such as substance addiction, impulsive behavior, and crime.
Hyperdopaminergic is the opposite condition, where excess dopamine levels are present within neurons. These also lead to complications, summarized below.