One type of photochemical reaction is the dissociation of a molecule into two fragments. Since it is the electrons that provide the bonding forces that hold atoms together into molecules, if the distribution of electrons within a molecule changes drastically, the bonding forces may also change.
Trade names: IntropinÂ®, DopastatÂ®, RevimineÂ®. Mechanistic Class: sympathomimetic, dopaminergic and Î² 1 -adrenergic agonist. Therapeutic Class: vasopressor. Mechanism of action: Dopamine is a natural catecholamine neurotransmitter and is the biological precursor to norepinephrine.It increases heart rate, cardiac contractility and blood pressure by multiple mechanisms. Dopamine causes norepinephrine release from sympathetic nerve endings.echanism of action: Dopamine is a natural catecholamine neurotransmitter and is the biological precursor to norepinephrine. It increases heart rate, cardiac contractility and blood pressure by multiple mechanisms.
For example, certain proteins such as the dopamine transporter (DAT), vesicular monoamine transporter 2 (VMAT 2), 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. Catechol O-methyl transferase (COMT) inhibitors such as entacapone and tolcapone, which are used in the treatment of Parkinson's disease. 2  Dopamine Î²-hydroxylase inhibitors like disulfiram (Antabuse), which can be used in the treatment of addiction to cocaine and similar dopaminergic drugs as a deterrent drug.