Neurons labeling with biocytin

Fig. 3. View of a single striatal spiny projection neuron, intracellularly filled with biocytin, in a sagittal section of the striatum (A) and at higher magnification (B). Corticofugal fiber fascicles are clearly evident coursing through the striatum. Spiny projection neurons are labeled within the striatum with calbindin iramunoreactiv-...

Since the neurons targeted by whole-cell patch clamp recording were also filled with biocytin (0.2 %) we were also able to identify the shape and position of these P -GFP neurons within the cortical network. We used streptavidin conjugated to a red fluorescent probe (Alexa 568). Streptavidin reacts directly with biotin (biocytin) within the filled neuron, labeling only the filled neuron in the red fluorescence channel of the wide-field microscope. Typically we obtained recovery percentages of 80-100 % of neurons using the protocol below. 

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