Luca, our lab focuses on the SNC and we have been using horizontal slices, mostly because ascending fibers toward the striatum lie somewhat horizontally. The SN is easy to identify visually while slicing. According to my experience staining these slices, most TH positive neurons are available rostral and caudal to the MT (medial terminal nucleus of the accessory optic tract) (See Paxinos and Watson rat atlas Bregma -8.10), just dorsal of the interpeduncular fossa. This is roughly midway through the SN. We typically use 200-250um for visual patch slices, and 300um for blind patching or microelectrode recordings. Best of luck.

Hi Adam,

thanks for youe answer. Today i tried horizontal slicing but with no good news. I have a lot of problems in identifying the region. I'm starting to think that the substantia nigra does not exist :p

Horizontal slices are definitely the way to go.  Don't be discouraged if the first slices aren't great. Utilize younger animals at first if possible, since the myelination will be less and image quality is typically better.  If you are using older animals, try cutting in NMDG-substituted solution and then briefly warming the slices (35 C for no more than 10 min), before storing in regular aCSF. The MT and pars reticulata should be readily visible in your sections.

 Luca, if you want. There are not many KM to see how to record from these cells.

Nicola

Hi Nicola,

thanks so much for your offer. Effectively Rome is not so far from Milan, considering also that my guides in exploring the substantia nigra world are several papers that you published. If is not a problem i'll write you soon.

Thanks so much and have a nice day.

Luca

You can come when you like, let us know 

Ciao

Nicola