Direct Evaluation of L-DOPA Actions on Neuronal Activity of Parkinsonian Tissue In Vitro

Figure 1

Control and dopamine-depleted striatal microcircuits. (a), (b) Raster plots showing spontaneous neuronal activity in striatal microcircuits in control (a) and after dopamine (DA) depletion (b). Note, increased activity in the DA-depleted circuit. (c), (d) Histograms of summed activity (columns) shown in raster plots frame by frame. Only the DA-depleted microcircuit had significant peaks of coactive neurons: peaks of synchronization of the same color indicate that similar neurons discharged in those instances. (e) Similarity indices of all neuronal vectors representing network states as a function of time in the DA-depleted circuit. (f) Multidimensional reduction of vectors representing network states using locally linear embedding (LLE). Note that one neuronal vector (red: projections of the peaks of synchronization above) activates more frequently creating a dominant network state that absorbs most active neurons. (g), (h) Cumulative activity and cumulative cell recruitment in both control (black traces) and DA-depleted circuit (red traces).