Long term high frequency stimulation of STN increases dopamine in the corpus striatum of hemiparkinsonian rhesus monkey

Mechanisms of High Frequency Stimulation of the Subthalamic Nucleus in Parkinson's Disease: From Local to Distal Effects on the Basal Ganglia Network

“…This hypothesis is supported by experimental data from in vivo microdialysis studies showing that STN-HFS increases the amounts of DA and its metabolites in the striatal extracellular compartment in normal and parkinsonian rats ( Fig. 5A and B) (Bruet et al, 2001;Meissner et al, 2001Meissner et al, , 2002 and monkeys (Zhao et al, 2009), probably through the direct or indirect activation of DAergic SNc neurons. These neurochemical results seem to be consistent with previous electrophysiological and anatomical studies showing a large increase in neural firing in the SNc DAergic neurons of 6-OHDA-treated rats immediately after the start of STN-HFS and the existence of moderate numbers of glutamatergic efferents from the STN projecting to the SNc with NMDA receptors located in their dendrites (Groenewegen & Berendse, 1990).…”

“…5A and C) and parkinsonian animals ( Fig. 5B and D) during STN-HFS (Bruet et al, 2001;Meissner et al, 2001Meissner et al, , 2002Zhao et al, 2009). As STN sends direct projections to the striatum (Nakano et al, 1990) and STN-HFS improves all motor symptoms and allows a considerable reduction of dopaminergic medication in parkinsonian patients, it has been suggested that the therapeutic action of STN-HFS may depend partly on changes in striatal DA transmission.…”

Real-time simultaneous recording of electrophysiological activities and dopamine overflow in the deep brain nuclei of a non-human primate with Parkinson’s disease using nano-based microelectrode arrays

“…The available physiological and anatomical studies strongly suggest that the pathologic feature of this disease is the progressive degeneration of nigral dopamine neurons, which leads to severe dopaminergic denervation of the corpus striatum. Morphological and neurochemical studies have found the marked and consistent reduction of the DA concentration in the striatum of PD patients 8,9 . As we know, in vivo extracellular DA contents are in the low nanomolar level.…”

Subthalamotomy-induced changes in dopamine receptors in parkinsonian monkeys

“…On the contrary, DA was decreased whereas DOPAC and HVA were increased by STN-HFS in full hemiparkinsonian rats, suggesting an elevated DA turnover (Meissner et al, 2002). In hemiparkinsonian MPTP monkey, unilateral subthalamic HFS also increased striatal DA ipsilateral to stimulation, both in short-and long-term stimulation (Zhao et al, 2009). On the other hand, no change was observed contralaterally (Zhao et al, 2009).…”