Pharmacological studies on the interrelation between the dopaminergic, GABAergic and opioid peptidergic systems in the central nervous system of the rat.

To elucidate the functional connections between dopaminergic, GABAergic and opioid peptidergic systems in rats, electrophysiological, behavioral, neurochemical and histological investigations have been undertaken, focusing on the changes in drug sensitivity in the central nervous system (CNS). Changes in sensitivity in the CNS can be induced by denervation, chronic administration of antagonists or agonists, and by the inhibition of the axoplasmic transport system. It is conceivable that the changes in sensitivity of the CNS to transmitters may be related to the etiology of mental illnesses such as schizophrenia and mania and may be related to the symptoms of Parkinson's disease. Investigation of changes in sensitivity of the CNS to transmitters or drugs may provide the key for elucidating the biological nature of mental illness.