Appreciation of the role of dopamine in the brain, as a transmitter and as a precursor of noradrenaline, came in mid-1960s when a combination of neurochemistry and neuropharmacology led to many important discoveries about the role of central nervous system transmitters, and about ability of drugs to influence these systems. There are three main dopaminergic pathways in the CNS: nigrostriatal, mesolimbic and tuberoinfundibular. There are two main families of dopamine receptor, D1 and D2, linked, respectively, to stimulation or inhibition of adenylate cyclase. There are further divided into subtypes. Most of the known functions of dopamine appear to be mediated by receptors of D2 family. Two main diseases are conected with dopamine and dopaminergic receptors: shizophrenia and Parkinson's disease. Shizophrenia is a psychotic illness characterised by delusions, hallucinations and thought disorder, together with social withdrawal and often dementia. Pharmacological evidence is generally consistent with dopamine overactivity hypothesis, but there is some evidence for involvement of serotonin􀄈rgic system. Neuroleptics, also known as antipsychotic agents, are used in the symptomatic management of psychoses, including shizophrenia and mania. They are believed to owe their action to competitive antagonist properties at dopaminergic receptors in the brain. Some neuroleptics are also been imployed in anesthetic procedures and in certain neuropsychiatric disorders. There are few main chemical categories of neuroleptic drugs: the so called, typical neuroleptics include the phenotiazines, the butyro- phenones, and the thioxantenes while »atypical« neuroleptics include the benzamides and the dibenzodiazepines. Parkinson's disease is associated with a deficiency of nigrostriatal dopaminergic neurons. lt is a progressive disorder of movement that occurs most commonly in the elderly, and the main symptoms are tremor, muscle rigidity and decreases in the frequency of voluntary movements. Drugs used in parkinsonism act by counteracting deficiency of dopamine in basa! ganglia, like L-dopa, bromocriptin, selegilin, or by blocking muscarinic receptors, like biperiden. Newer drugs act by blocking N-metyl- D-aspartat (NMDA) receptors for aminoacids glutamat and aspartat. Both, antiparkinsonic drugs as well as neuroleptics cause many side effects that must be treated properly. For example, L-dopa may cause aritmia, nausea, vomiting, hypotension and neuropleptics often cause, the so-c.alled extrapiramidal symptoms which include parkinsonism, akatisia, tardive diskinesia. That is the reason why the investigation of new drugs with specific act and minimal side-effects is in permanent progress.