In-vivo deep brain recordings of intranigral grafted cells in a mouse model of Parkinson's disease.

We recently showed that intranigral transplantation of embryonic neurons in a mouse model of Parkinson's disease led to anatomical and functional recovery of the nigrostriatal pathway. Here we report, in-vivo electrophysiological characteristics of these grafted neurons 2 months after transplantation. Extracellular activity was mapped within the transplant using microarray electrodes and exploration was done with antidromic and orthodromic striatal stimulation. Grafted neurons expressed spontaneous electrophysiological activity with dopaminergic-like characteristics, and antidromic and orthodromic responses suggest a functional recovery of the nigrostriatal loop.