The<unk>  receptors are 7-transmembrane domains and are members of the G protein-coupled receptors (GPCR) superfamily.<unk>  receptors have five subtypes, D1 through D5, the subtypes can be divided into two subclasses due to their mechanism of action on adenylate cyclase enzyme, D1-like receptors (D1 and D5) and D2-like receptors (D2, D3 and D4). D1-like receptors are primarily coupled to Gαs/olf proteins and activates adenylate cyclase which increases intracellular levels of cAMP, they also activate the Gβγ complex and the N-type Ca2+ channel. D2-like receptors decrease intracellular levels of the second messenger cAMP by inhibiting adenylate cyclase. Bromocriptine Bromocriptine is an ergot derivative, semi-synthetic. Bromocriptine is a D2 receptor agonist and D1 receptor antagonist with a binding affinity to D2 receptors of anterior pituitary cells, exclusively on lactotrophs. Bromocriptine stimulates Na+, K+-ATPase activity and/or cytosolic Ca2+ elevation and therefore reduction of prolactin which leads to no production of cAMP. Pramipexol Pramipexol is a highly active non-ergot D2-like receptor agonist with a higher binding affinity to D3 receptors rather than D2 or D4 receptors. The mechanism of action of pramipexole is mostly unknown, it is thought to be involved in the activation of<unk>  receptors in the area of the brain where the striatum and the substantia nigra is located. This stimulation of<unk>  receptors in the striatum may lead to the better movement performance.
Dopamine agonist
Dopamine antagonist
Alpha-adrenergic agonist
Norepinephrine–dopamine disinhibitor
Muscarinic antagonist
Beta-adrenergic agonist
Serotonin receptor agonist
Orexin antagonist