Also, previous studies by von Bohlen et al. (2006)
http://plosone.org/article/info:doi/10.1371/journal.pone.0000573#article1.body1.sec3.sec2.p1
The reference given in 21 is not corect; the authorsa are
von Bohlen Und Halbach O, Hinz U, Unsicker K, Egorov AV.
There is no study from 2006 from these authors concerning TRPC in theSubstantia nigra
2006 there is a paper by DeMarch et al on TRPC5 in theSubstantia nigra
De March,Z., Giampa,C., Patassini,S., Bernardi,G., and Fusco,F.R. (2006). Cellular localization of TRPC5 in the substantia nigra of rat. Neurosci Lett. 402, 35-39.