Role of serotonergic neurons in L-DOPA-derived extracellular dopamine in the striatum of 6-OHDA-lesioned rats

Hiroyasu Tanaka, Kazuya Kannari, Tetsuya Maeda, Masahiko Tomiyama, Toshihiro Suda, Muneo Matsunaga
1999 NeuroReport  
THE effect of L-dihydroxyphenylalanine (L-DOPA) on extracellular dopamine (DA) in the striatum was determined by microdialysis in 6-hydroxydopamine (6-OHDA)-lesioned rats treated with and without the serotonergic neurotoxin 5,7-dihydroxytryptamine (5,7-DHT). At the same time the intensity of L-DOPAinduced rotational behavior was assessed. In 6-OHDAlesioned rats treated with 5,7-DHT, L-DOPA (50 mg/ kg, i.p.) increased extracellular DA only to 20% of that measured in animals not treated with
more » ... t treated with 5,7-DHT. Likewise, 6-OHDA-lesioned rats treated with 5,7-DHT exhibited a signi®cantly lower number of L-DOPAinduced rotations. These results suggest that serotonergic terminals in the striatum can convert exogenously administered L-DOPA into DA that can be released into the extracellular space. NeuroReport 10:631±634 #
doi:10.1097/00001756-199902250-00034 pmid:10208602 fatcat:2ojdu272m5f2xo2lzzodbsdvwe