Hang on- it’s a long one!
It is the end of week 3, and I could write a book on how much I’ve learned over this time that has gone so quickly. Slowly I’ve become more independent in the lab being able to carry myself with confidence and complete my task without the security blanket of my mentor presiding over my every move. Last week I observed as a doctoral student in my lab performed surgeries on her rats to implant the electrodes that will be used for stimulation. With my overall career goal being to become a neurosurgeon, this was especially interesting to me and hopefully one day I will be able to try my hand at implantation.
So far I have been working slightly backwards on my quest to contribute to the alleviation the devastating side effects of Parkinson’s disease. My job for the past 2 weeks has been working as a histologist (histology is the post-mortem examination of tissue and cell). I spent my time analyzing brain tissue samples from previous rats that have been lesioned to simulate the effect of Parkinson’s disease and then treated with deep brain stimulation (DBS). The brain sections are only 50 micron thick, nearly transparent and extremely fragile and learning to handle them was my first challenging task.
To analyze the tissue we treat the samples with different stains to tag different areas we are interested in. We use a nuclear stain to tag the areas of the brain that are heavily nucleated or dense with neurons (the area of the brain that we aim to place the electrode well nucleated) and immunohistochemistry (IHC) staining to tag the protein tyrosine hydroxylase (TH), which is a precursor to dopamine, the neurotransmitter that controls motor function). The nuclear stain is a rather simple process, but the IHC staining is a grueling and very specific 3-day process of incubation periods and PBS washes all in the hopes of seeing brown spots on your brain tissue in the end. After the samples are stained we can use the microscope to identify the different areas of the brain and find the track of the DBS electrodes and see if they were places properly. While examining my tissue I was able to get some very successful stains that showed the lesions in the brain as well as the areas that were producing high amounts of TH. See picture below:
(brown is TH and purple areas are nucleated)
Although it required a lot of patience, seeing the finished product was very rewarding and I even got a hearty good job from my mentor after he examined the samples. I look forward to getting more experience and lab work done as we begin behavioral studies and analysis of a new batch of rats that have just finished recovering from surgery. I’ll keep you posted =)