these findings suggest that ( 1 ) the dopamine receptors mediating yawning and stereotypy have different anatomical locations ( 2 ) ageing is associated with decreased responsiveness to stimulation of dopamine autoreceptors , consequent upon the loss of dopaminergic nerve terminals , and ( 3 ) while the functional response to selective stimulation of postsynaptic d2 receptors decreases with age , the postsynaptic response to a mixed d1/d2 agonist increases .
C0034798
dopamine
C0058698
d2 receptors