Interrelationship between activation of dopaminergic pathways and cerebrospinal fluid concentration of dopamine tetrahydroisoquinoline metabolite salsolinol in humans: preliminary findings.

The main objective of this study was to determine whether the activation of dopaminergic pathways, through adrenal-caudate transplantation, stimulated the production of dopamine and salsolinol in cerebrospinal fluid (CSF) of patients with Parkinson's disease. Dopamine sulfate and salsolinol sulfate in CSF specimens were measured by radioenzymatic technique. The results of this study demonstrated that the replacement of degenerative nigrostriatal neurons with new dopamine-producing cells by adrenal brain transplants in patients with Parkinson's disease resulted in significant increase (p less than 0.05) in CSF levels of free dopamine, dopamine sulfate, free salsolinol, and salsolinol sulfate as compared with preoperative levels. Moreover, the oral administration of L-dopa to these transplanted patients caused substantial (p less than 0.001) elevation in CSF levels of free dopamine (before L-dopa, 146 +/- 57 pg/ml; after L-dopa, 575 +/- 207 pg/ml), dopamine sulfate (before L-dopa, 1966 +/- 945 pg/ml; after L-dopa, 41679 +/- 29326 pg/ml), free salsolinol (before L-dopa, 43 +/- 29 pg/ml; after L-dopa, 186 +/- 90 pg/ml), and salsolinol sulfate (before L-dopa, 405 +/- 477 pg/ml; after L-dopa, 2908 +/- 2572 pg/ml), respectively.