Multiple dopamine receptors and their implications in medicine.

Two categories of dopamine receptor were identified with classical pharmacological and biochemical techniques. Five different molecular species of dopamine receptor have been identified with molecular biological techniques. Each of the these five receptors can be assigned to one of the two classically identified dopamine receptor categories. The biology of the dopamine receptors can be investigated with molecular biological techniques. Recent pharmacological investigations show that the D1 dopamine receptor may be an important site of action for antiparkinsonian drugs.